Moved vendored js/css into public/vendor and documented sources (#1484) (#2241)

* Cleaning up public/ and documenting js/css libs.

This commit mostly addresses #1484 by moving vendor'ed plugins into a
vendor/ directory and documenting their upstream source and license in
vendor/librejs.html.

This also proves gitea is using only open source js/css libraries which
helps toward reaching #1524.

* Removing unused css file.

The version of this file in use is located at:
  vendor/plugins/highlight/github.css

* Cleaned up librejs.html and added javascript header

A SafeJS function was added to templates/helper.go to allow keeping
comments inside of javascript.

A javascript comment was added in the header of templates/base/head.tmpl
to mark all non-inline source as free.

The librejs.html file was updated to meet the current librejs spec. I
have now verified that the librejs plugin detects most of the scripts
included in gitea and suspect the non-free detections are the result of
a bug in the plugin. I believe this commit is enough to meet the C0.0
requirement of #1534.

* Updating SafeJS function per lint suggestion

* Added VERSIONS file, per request

public/vendor/plugins/codemirror/mode/commonlisp/commonlisp.js

@@ -0,0 +1,123 @@
+// CodeMirror, copyright (c) by Marijn Haverbeke and others
+// Distributed under an MIT license: http://codemirror.net/LICENSE
+
+(function(mod) {
+  if (typeof exports == "object" && typeof module == "object") // CommonJS
+    mod(require("../../lib/codemirror"));
+  else if (typeof define == "function" && define.amd) // AMD
+    define(["../../lib/codemirror"], mod);
+  else // Plain browser env
+    mod(CodeMirror);
+})(function(CodeMirror) {
+"use strict";
+
+CodeMirror.defineMode("commonlisp", function (config) {
+  var specialForm = /^(block|let*|return-from|catch|load-time-value|setq|eval-when|locally|symbol-macrolet|flet|macrolet|tagbody|function|multiple-value-call|the|go|multiple-value-prog1|throw|if|progn|unwind-protect|labels|progv|let|quote)$/;
+  var assumeBody = /^with|^def|^do|^prog|case$|^cond$|bind$|when$|unless$/;
+  var numLiteral = /^(?:[+\-]?(?:\d+|\d*\.\d+)(?:[efd][+\-]?\d+)?|[+\-]?\d+(?:\/[+\-]?\d+)?|#b[+\-]?[01]+|#o[+\-]?[0-7]+|#x[+\-]?[\da-f]+)/;
+  var symbol = /[^\s'`,@()\[\]";]/;
+  var type;
+
+  function readSym(stream) {
+    var ch;
+    while (ch = stream.next()) {
+      if (ch == "\\") stream.next();
+      else if (!symbol.test(ch)) { stream.backUp(1); break; }
+    }
+    return stream.current();
+  }
+
+  function base(stream, state) {
+    if (stream.eatSpace()) {type = "ws"; return null;}
+    if (stream.match(numLiteral)) return "number";
+    var ch = stream.next();
+    if (ch == "\\") ch = stream.next();
+
+    if (ch == '"') return (state.tokenize = inString)(stream, state);
+    else if (ch == "(") { type = "open"; return "bracket"; }
+    else if (ch == ")" || ch == "]") { type = "close"; return "bracket"; }
+    else if (ch == ";") { stream.skipToEnd(); type = "ws"; return "comment"; }
+    else if (/['`,@]/.test(ch)) return null;
+    else if (ch == "|") {
+      if (stream.skipTo("|")) { stream.next(); return "symbol"; }
+      else { stream.skipToEnd(); return "error"; }
+    } else if (ch == "#") {
+      var ch = stream.next();
+      if (ch == "[") { type = "open"; return "bracket"; }
+      else if (/[+\-=\.']/.test(ch)) return null;
+      else if (/\d/.test(ch) && stream.match(/^\d*#/)) return null;
+      else if (ch == "|") return (state.tokenize = inComment)(stream, state);
+      else if (ch == ":") { readSym(stream); return "meta"; }
+      else return "error";
+    } else {
+      var name = readSym(stream);
+      if (name == ".") return null;
+      type = "symbol";
+      if (name == "nil" || name == "t" || name.charAt(0) == ":") return "atom";
+      if (state.lastType == "open" && (specialForm.test(name) || assumeBody.test(name))) return "keyword";
+      if (name.charAt(0) == "&") return "variable-2";
+      return "variable";
+    }
+  }
+
+  function inString(stream, state) {
+    var escaped = false, next;
+    while (next = stream.next()) {
+      if (next == '"' && !escaped) { state.tokenize = base; break; }
+      escaped = !escaped && next == "\\";
+    }
+    return "string";
+  }
+
+  function inComment(stream, state) {
+    var next, last;
+    while (next = stream.next()) {
+      if (next == "#" && last == "|") { state.tokenize = base; break; }
+      last = next;
+    }
+    type = "ws";
+    return "comment";
+  }
+
+  return {
+    startState: function () {
+      return {ctx: {prev: null, start: 0, indentTo: 0}, lastType: null, tokenize: base};
+    },
+
+    token: function (stream, state) {
+      if (stream.sol() && typeof state.ctx.indentTo != "number")
+        state.ctx.indentTo = state.ctx.start + 1;
+
+      type = null;
+      var style = state.tokenize(stream, state);
+      if (type != "ws") {
+        if (state.ctx.indentTo == null) {
+          if (type == "symbol" && assumeBody.test(stream.current()))
+            state.ctx.indentTo = state.ctx.start + config.indentUnit;
+          else
+            state.ctx.indentTo = "next";
+        } else if (state.ctx.indentTo == "next") {
+          state.ctx.indentTo = stream.column();
+        }
+        state.lastType = type;
+      }
+      if (type == "open") state.ctx = {prev: state.ctx, start: stream.column(), indentTo: null};
+      else if (type == "close") state.ctx = state.ctx.prev || state.ctx;
+      return style;
+    },
+
+    indent: function (state, _textAfter) {
+      var i = state.ctx.indentTo;
+      return typeof i == "number" ? i : state.ctx.start + 1;
+    },
+
+    closeBrackets: {pairs: "()[]{}\"\""},
+    lineComment: ";;",
+    blockCommentStart: "#|",
+    blockCommentEnd: "|#"
+  };
+});
+
+CodeMirror.defineMIME("text/x-common-lisp", "commonlisp");
+
+});