Update content_script.js

Preserve capitalization
Merge pull request #2 from coffeeworks/patch-1

Update content_script.js (preserve capitalization)
preserve capitalization
improved case preservation
Update README.md
Update README.md
Added link to Firefox port

Because some people still use Firefox, despite my best efforts to persuade them not to
Ugh, fix the extension's handywork

duhhhhh
Merge pull request #6 from DaveRandom/patch-2

Added link to Firefox port
Update README.md
Changing regex
Even more awesome
Fix
All kinds of mistakes today
Fix - b = <
Slight change
Missed a comma
Fixing CRX
Making match global
New CRX