Currently, the regex causes the following error:
Uncaught Error: target of repeat operator is not specified
```
At /usr/lib/atom/node_modules/first-mate/lib/scanner.js:31
Error: target of repeat operator is not specified
at Scanner.module.exports.Scanner.createScanner (/usr/lib/atom/node_modules/first-mate/lib/scanner.js:31:24)
at Scanner.module.exports.Scanner.getScanner (/usr/lib/atom/node_modules/first-mate/lib/scanner.js:37:31)
at Scanner.module.exports.Scanner.findNextMatch (/usr/lib/atom/node_modules/first-mate/lib/scanner.js:56:22)
at Rule.module.exports.Rule.findNextMatch (/usr/lib/atom/node_modules/first-mate/lib/rule.js:98:28)
at Rule.module.exports.Rule.getNextTags (/usr/lib/atom/node_modules/first-mate/lib/rule.js:154:21)
at Grammar.module.exports.Grammar.tokenizeLine (/usr/lib/atom/node_modules/first-mate/lib/grammar.js:162:44)
at TextMateLanguageMode.buildTokenizedLineForRowWithText (/usr/lib/atom/src/text-mate-language-mode.js:503:46)
at TextMateLanguageMode.buildTokenizedLineForRow (/usr/lib/atom/src/text-mate-language-mode.js:488:17)
at TextMateLanguageMode.tokenizeNextChunk (/usr/lib/atom/src/text-mate-language-mode.js:340:41)
at _.defer (/usr/lib/atom/src/text-mate-language-mode.js:324:57)
at /usr/lib/atom/node_modules/underscore/underscore.js:768:19
```
Fix the regex by applying the following modifications:
* use double backslashes to escape special characters
* insert missing * into regex
While here, also give the pattern a .acme suffix as all the other have.
