Bump Homebrew to 0.7.1

The Homebrew version number is mainly useful for bug reports. Since it is
included in "brew --config" output, it is an easy way to see roughly how
new the a user's version of Homebrew is.

Bumping the micro version now, in anticipation of some more version-changing
events in the near future.

Library/Homebrew/global.rb

@@ -5,7 +5,7 @@ require 'utils'
 
 ARGV.extend(HomebrewArgvExtension)
 
-HOMEBREW_VERSION = 0.7
+HOMEBREW_VERSION = '0.7.1'
 HOMEBREW_WWW = 'http://mxcl.github.com/homebrew/'
 
 if Process.uid == 0