Add wiki URLs to console output; fixes #342

Note this will only work in the browser.
Also adds a `url` property to LintError & LintWarning.

Closes #353

src/bootlint.js

@@ -60,6 +60,7 @@ var LocationIndex = _location.LocationIndex;
         'script[src$="/bootstrap.min.js"]',
         'script[src="bootstrap.min.js"]'
     ].join(',');
+    var WIKI_URL = 'https://github.com/twbs/bootlint/wiki/';
 
     function compareNums(a, b) {
         return a - b;
@@ -269,6 +270,7 @@ var LocationIndex = _location.LocationIndex;
      */
     function LintError(id, message, elements) {
         this.id = id;
+        this.url = WIKI_URL + id;
         this.message = message;
         this.elements = elements || cheerio('');
     }
@@ -282,6 +284,7 @@ var LocationIndex = _location.LocationIndex;
      */
     function LintWarning(id, message, elements) {
         this.id = id;
+        this.url = WIKI_URL + id;
         this.message = message;
         this.elements = elements || cheerio('');
     }
@@ -1189,10 +1192,10 @@ var LocationIndex = _location.LocationIndex;
                     }
 
                     if (!lint.elements.length) {
-                        console.warn("bootlint: %c " + lint.id + " ", background, lint.message);
+                        console.warn("bootlint: %c " + lint.id + " ", background, lint.message + " Documentation: " + lint.url);
                     }
                     else {
-                        console.warn("bootlint: %c " + lint.id + " ", background, lint.message + '\n', lint.elements);
+                        console.warn("bootlint: %c " + lint.id + " ", background, lint.message + " Documentation: " + lint.url, lint.elements);
                     }
                     errorCount++;
                 };