(manually tested)
- new rc var: GL_BINDIR2; see doc update in this commit
- added _which() function to search both $GL_BINDIR and $GL_BINDIR2
- 'gitolite <command>', non-perl triggers, VREFs, and sugar, use this
- unshifted $GL_BINDIR2/lib into @INC upfront in Rc.pm
- perl triggers use this
Using a g2-style "chained update hook" as a VREF doesn't *quite* work:
- all STDOUT from the hook is lost
- worse, all lines get parsed as a ref followed by a message, and if
the ref doesn't look like a ref it dies
So now we do all this only if the message starts with 'VREF/'. Any
other output is just printed out as is.
