Add feature: guiguan#53

Add feature: allow update of the header with not only  "@" but also other char.

- `#` for languages like Python
- `*` for languages like C
- `-` for languages like Haskell
- `;` for languages like lisp

Thought it works well on my Mac, I am still not sure whether it would cause any problem or not.

lib/file-header.coffee

@@ -263,7 +263,7 @@ module.exports = FileHeader =
   # the corresponding header template is presented
   hasHeader: (editor, buffer, headerTemplate) ->
     # these placeholder preambles are used as anchor points in source code scanning
-    if !(preambles = headerTemplate.match(/@[^:]+:/g))
+    if !(preambles = headerTemplate.match(/[@-#;\*\\][^:]+:/g))
       return false
     preambles = preambles.map(@escapeRegExp)
     re = new RegExp(preambles.join('|'), if atom.config.get('file-header.ignoreCaseInTemplateField', scope: (do editor.getRootScopeDescriptor)) then 'gi' else 'g')
@@ -276,7 +276,7 @@ module.exports = FileHeader =
 
   updateField: (editor, placeholder, headerTemplate, buffer, newValue) ->
     escaptedPlaceholder = @escapeRegExp(placeholder)
-    re = new RegExp(".*(@[^:]+:).*#{ escaptedPlaceholder }.*(?:\r\n|\r|\n)", 'g')
+    re = new RegExp(".*([@-#;\*\\][^:]+:).*#{ escaptedPlaceholder }.*(?:\r\n|\r|\n)", 'g')
     # find anchor point and line in current template
     while match = re.exec(headerTemplate)
       anchor = match[1]