New icon added

Couldn't wait for Sencha to get back to me about using their logo
anymore
Only CSS beautify if it's a CSS file
No margin needed on new icon
Reduce content height by 2px for bottom bar
Remove empty lines on cursor move

beforeSelectChange stores the previous line number
On cursor activity now it works out if the line we were on would be
empty if we removed white space and if so, clear the line