Update dependencies for GSL 2.0.

Starting with gsl (2.0+dfsg-1) the libgsl0-dev package has been renamed
to libgsl-dev, and libgsl0-dev is provided by libgsl-dev for transition
purposes.

libgsl-dev is likely to stop providing libgsl0-dev in the future. To
remain compatible with both GSL 1.x and 2.0 packaging libgsl-dev is now
the preferred (build) dependency, when it's not available libgsl0-dev will
be used instead.

Author: sebastic

debian/control.in

@@ -17,7 +17,7 @@ Build-Depends:
 #saucy# libgdal-dev (>= 1.9.0),
 #wheezy# libgdal1-dev,
  libgeos-dev (>= 3.0.0),
- libgsl0-dev,
+ libgsl-dev | libgsl0-dev,
  libpq-dev,
  libproj-dev,
  libqt4-dev (>= 4.7.0),
@@ -241,7 +241,7 @@ Depends:
 #saucy# libgdal-dev (>= 1.9.0),
 #wheezy# libgdal1-dev,
  libgeos-dev (>= 3.0.0),
- libgsl0-dev,
+ libgsl-dev | libgsl0-dev,
  libpq-dev,
  libproj-dev,
  libqgis-app{QGIS_ABI} (= ${binary:Version}),