Quoted strings are now coloured

Differentiates the string from surrounding object properties or
function calls in JS (probably other languages too).

Thanks to @jessefalzone for the colour
Fixed the preserve case icon and resized the replace button.
Fix path issue with Package Control installations

Fixes #44.
Merged Pull Requests of original repo
Changed diff colors - especially for GitGutter
Added default color for BracketHighlighter
Merge remote-tracking branch 'jessefalzone/master'
Merge remote-tracking branch 'kevva/fix'
Fixing conflicts and tons of merges