GSL git setup

[Patrick Alken]

Hello all,

  As some of you may know, we recently switched the GSL repository on 
savannah to use git instead of bzr. We currently have two main branches:

master - this will contain all new development features leading 
eventually to version 2.0. I have already incorporated the ALF extension 
into it for associated legendre functions, which required a new API that 
will not be backward compatible with the 1.x series. The old API is 
still available but marked as deprecated. We anticipate several further 
changes which will also change APIs.

maint-1 - this is the 1.x maintenance branch which will not be actively 
developed, but if there are any bug fixes required, we can easily use it 
to make another 1.x release

Anyone who would like to develop new features and submit patches please 
use the master branch for your work.

Thanks,
Patrick