Default to sRGB colors for CSI RGB values.

- By default consider CSI 24-bit RGB values to be display independent
  sRGB colors.
- Add an advanced option to disable this and consider the values to
  be calibrated to the given display that iTerm2 is running on.
add comment about colorspace
Merge branch 'master' into sRGB
update project
10.7 target
Merge branch 'origin/master'
remove XXX comment
only do shift code once
merge
remove comment
update prefrence description
Merge branch 'master' into sRGB
remove 10.10 target
use sRGB for 24-bit color CSI values
backout change to always use sRGB for 24-bit color CSI values
Merge branch 'sRGB' of github.com:choppsv1/iTerm2 into sRGB
Merge pull request #176 from choppsv1/sRGB

Use sRGB colorspace for CSI 24-bit RGB colors.