more version magic for Mac and Windows installers

[Cristian Ionescu-Idbohrn]

On Sat, 23 Feb 2013, Dirk Hohndel wrote:
>
> As the commit message says, I would like people who are better in shell
> programming to review this code - this isn't supposed to be a "best
> shell script contest winner", but should work and be reasonably robust.

AFAICT, this is what you want:

	linux:  3.0-19-g0dc8e7b0a7c4
	darwin: 3.0.19
	win:    3.0.19.0

	linux:  3.0.1
	darwin: 3.0.1
	win:    3.0.1.0

	linux:  3.0
	darwin: 3.0.0
	win:    3.0.0.0

3 small patches comming upp:

7d92d1b Replace the '==' bashism with the posix equivalent '='.
87aa7e4 Use a posix equivalent solution instead of the pattern substitution bashism.
0dc8e7b Remove more useless quotes.


Cheers,

-- 
Cristian