Checks for Ruby version

[zshenker]

Zenflow does not work with Ruby earlier than 1.9, it would be nice to check if the Ruby version is older and throw errors and exit out earlier in this case(i.e. running on Ruby 1.8x)

Also on systems where there is rvm installed is there any way that the zenflow bin file can specify that it should run on a Ruby 1.9 or 2.0 if it exists on the system?

It is the use of Ruby 1.9+ new hash syntax that makes Zenflow incompatible with earlier versions.