get rid of double "shopt nullglob"!
Fix #48; bump version up to 0.4.1
Tweak README: line spacing!
Improve README: add special note and section about environment variables in Usage section!
Tweak README
update 'Fix #48' patch after rehash fix for rbenv got pushed in (caa4a8e228808b7e3dc1fdaf11c3d2ebac30296a)!
Tweak README
Rewrite rbenv-gemset-list; fix problems with handling spaces in pathnames (closes #49)
list project gemsets as well; first draft of behaviour
Improve README: '**Special environment variable tips and tricks**' section
Tweak README
Fix #53: bring in standard library gems for Rubinius! Bump version to 0.4.2
Tweak Rubinius fix to be more generic: bring in the ruby's standard gem path! (thanks to @felix125 for not letting go of this!)

Bump version to 0.5.0.
Fix previous fix (a91d8af3f0f67b62ad5ff28245c16a7be05967c2), and close #56. Thanks to @neovatar for reporting this, and for doing a lot of the hard work!

Bump version to 0.5.1.
ARGH, my bad! Correction to the previous fix: we should rely on "gem env gemdir", which is more reliable across the board (see, for example, Rubinius!).
Fix to previous fix again; thanks to @neovatar for pointing out that some folks apparently will have installs of jruby accessible by calling `ruby`!
Tweak README
Bump version to 0.5.3 to in incorporate all the latest fixes (jruby gotcha! https://github.com/sstephenson/ruby-build/issues/471)
Shortcut rbenv exec hook execution if we've already executed it earlier!

Net effect: PATH is kept at its "lean length" through repeated recursions of rbenv/-gemset; and GEM_PATH and GEM_HOME are not unnecessarily torn down and re-setup every time.
Update README to include download option off github.