bin/jruby script has incompatible bourne shell syntax

Error when running 'bin/jruby' -

bin/jruby: 55: function: not found
bin/jruby: 60: Syntax error: "}" unexpected

Cause:

The shebang line for bin/jruby says '#!/bin/sh'. On many systems, this will be a shell that supports the more modern function definition syntax for bourne-like shells, but on Ubuntu and maybe Debian, this shell is "dash" which is a very minimally-featured shell which fails on this syntax.

Simple example failing in /bin/sh:

% /bin/sh -c 'function foo { echo OK } &&  foo'  
/bin/sh: function: not found

Patches for this:

• (jruby-1_6 branch) https://github.com/jruby/jruby/pull/86
• (master branch ) https://github.com/jruby/jruby/pull/87