Escape "$" in labels, so preg_replace() doesn't remove it

I noticed that the "$" would get dropped from my labels, because of the preg_replace() action that was being called.  Escaping the character seems to solve the issue.
Merge pull request #33 from hsubu/patch-1

Escape "$" in labels, so preg_replace() doesn't remove it
Merge branch 'master' of git://github.com/slywalker/cakephp-plugin-boost_cake
Update README.md

Fixed typo
add test case checkbox label escape
Merge pull request #34 from steveperrycreative/master

Update README.md
fixed Issue #35
modified example
travis - add PHP 5.5
Merge pull request #36 from sasezaki/patch-1

travis - add PHP 5.5
Add test case for Issue #37
Fixed BoostCaeFormHelper
Merge pull request #43 from happyquality/fixMultipleCheckboxSpike

Fixed BoostCaeFormHelper
Merge branch 'master' of git://github.com/slywalker/cakephp-plugin-boost_cake
fixed for code standard
add test case and fixed bug
Set label text without having to create array 'text' key.
Fix test case for CakePHP 2.4.4.
Merge pull request #47 from wvdongen/master

Set label text without having to create array 'text' key.
Suggested repo is now twbs/bootstrap.