Strongly recommended adding color support about google-glog HOT 6 CLOSED

This might be a good idea to support colors. However, I'm not sure if it's 
trivial to 
implement this feature portably (we may need to check termcap/terminfo?). This 
will 
take long time for me. Patches are welcomed :)

Attached is a patch for part of this issue - it optionally makes FATAL & ERROR 
message red, and WARNING yellow when logging to stderr, -colorstderr is passed 
_and_ the current terminal supports colored output.  It does not color any VLOG 
output.

I should emphasise that in terms of work most of the legwork in this patch is 
taken from the gtest project (and thus license compatible etc).  I'm only 
responsible for plumbing it into glog (I'll let others judge how cleanly :P)

I have tested it against the latest in SVN (Rev 121) on OS X (10.7.x) & Ubuntu 
12.04 - although I don't have access to a Windows box, the code for Windows 
colorisation is taken directly from gtest and so I strongly suspect it will 
work, but I haven't tested it.

Great!

Could you sign our Contributor License Agreement, please? It
seems that we need to ask you to sign this to avoid any troubles. The
process is just submitting an HTML form, and it shouldn't take your
time so much.

http://code.google.com/legal/individual-cla-v1.0.html

Please note that these forms do not transfer copyright: the
contributor retains her ownership in the work. The CLA just grants
Google a "perpetual, non-exclusive, royalty-free, etc..." right to use
the work, sublicense it, and so on.

CLA signed (electronically) - let me know if there's anything else I need to do.

Done by http://code.google.com/p/google-glog/source/detail?r=123

I modified this patch by

http://code.google.com/p/google-glog/source/detail?r=124

Note that I renamed the name of flag (colorstderr => colorlogtostderr) because 
original name sounds a bit too general.