Revert Gem::Ext::BuildError change
Revert Gem::Ext::BuildError change

I tested this in `irb`, but when I ran Command-T, it dies with:

  NameError: uninitialized constant Gem::Ext

So will have to try again.

wincent/command-t,wincent/command-t,mtimkovich/command-t,wincent/command-t,yrro/command-t,mtimkovich/command-t,yrro/command-t