New rbfu invocation style

gistfile1.txt

# So here's the new rbfu invocation style I'm tinkering with.
# If you want to play around with it, you can get it from the
# 'rbfu-exec' branch in rbfu:
#
# https://github.com/hmans/rbfu/tree/rbfu-exec
#
# The overall syntax is:
#
#     rbfu [@<version>] <command>
#
# Or, if you want to switch to the specified version in your current
# shell environemnt:
#
#     rbfu-env [@<version>] 
#
# The @<version> parameter is optional - if you don't specify it, rbfu will
# look for ./.rbfu-version and ~/.rbfu-version.

$ ruby -v
ruby 1.8.7 (2011-06-30 patchlevel 352) [i686-darwin11.2.0]

$ rbfu @jruby ruby -v
Activated Ruby jruby. (from command line)
jruby 1.6.5 (ruby-1.8.7-p330) (2011-10-25 9dcd388) (Java HotSpot(TM) 64-Bit Server VM 1.6.0_29) [darwin-x86_64-java]

$ ruby -v
ruby 1.8.7 (2011-06-30 patchlevel 352) [i686-darwin11.2.0]

$ rbfu-env @jruby
Activated Ruby jruby. (from command line)

$ ruby -v
jruby 1.6.5 (ruby-1.8.7-p330) (2011-10-25 9dcd388) (Java HotSpot(TM) 64-Bit Server VM 1.6.0_29) [darwin-x86_64-java]