raising wrong exception when system command fails

[pitluga]

We see this method when a push is rejected on jruby 1.6.7.2

sanitized output:

Finished in 57.77 seconds
743 examples, 0 failures, 5 pending
To git@example.com:repo.git
! [rejected] master -> master (non-fast-forward)
error: failed to push some refs to 'git@example.com:repo.git'
To prevent you from losing history, non-fast-forward updates were rejected
Merge the remote changes (e.g. 'git pull') before pushing again. See the
'Note about fast-forwards' section of 'git push --help' for details.
RuntimeError: No current exception

RuntimeError: No current exception
system at ruby/gems/1.8/gems/rake_commit-0.11.0/lib/shell.rb:6
push at ruby/gems/1.8/gems/rake_commit-0.11.0/lib/git.rb:63
commit at ruby/gems/1.8/gems/rake_commit-0.11.0/lib/git.rb:15
commit at ruby/gems/1.8/gems/rake_commit-0.11.0/lib/commit.rb:47
(root) at ruby/gems/1.8/gems/rake_commit-0.11.0/bin/rake_commit:
load at org/jruby/RubyKernel.java:1068
(root) at bin/rake_commit:23

the code just does a plain raise instead of passing a string. This causes an exception since their is no current exception to re-raise. You get the desired behavior, just a weird error.