Fix argument passing when overcommit-hook updated

This was a nasty one. In a nutshell, any post-checkout hook would fail
seemingly at random due to command-line arguments not being passed to
it (which should _never_ happen with `post-checkout` hooks).

It turns out that this was caused by the code in `overcommit-hook` which
re-`exec`s the master hook if it was updated before the run. Since we
were passing `$0` (i.e. the master hook script) to `exec` instead of
`$0 $*` (i.e. the master hook script along with all command line
arguments) those arguments were getting lost, causing the post-checkout
hook to fail.

Change-Id: I5a7946c43b772d4a2c0bd68a70e3efc225cd8798
Reviewed-on: http://gerrit.causes.com/40970
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane.dasilva@brigade.com>

Author: sds

CHANGELOG.md

@@ -5,6 +5,8 @@
 * Fix bug where incorrect "hook run interrupted" message displayed when
   hook run failed
 * Gracefully handle `git stash` failures in pre-commit hook runs
+* Fix `overcommit-hook` auto-updating not passing original arguments to
+  updated hook
 
 ## 0.14.1
 

template-dir/hooks/overcommit-hook

@@ -55,7 +55,7 @@ begin
   # Ensure master hook is up-to-date
   installer = Overcommit::Installer.new(logger)
   if installer.run(Overcommit::Utils.repo_root, :action => :update)
-    exec $0 # Execute the updated hook
+    exec($0, *ARGV) # Execute the updated hook with all original arguments
   end
 
   config = Overcommit::ConfigurationLoader.load_repo_config