Replace PrepareNibs.py with PrepareNibs.rb
update prepare_command to reference prepareNibs.rb
Deprecates previous python install script
Merge remote-tracking branch 'origin/New-ruby-prepareNibs' into 0.5.52
0.6.52 RC
0.6.52 RC
Update change log to explain new prepare nibs script
Update change log with upgrade instructions for PrepareNibs
add link to manual instal process
Merge pull request #17 from optimizely/0.6.52

0.6.52