Fix #1429: Remove git dep from gettext; break circular dependency.

- It's not really a circular dependency -- git is a run dependency of gettext

- We can revert this change when Spack is smart enough to make git a run
  dependency and build it.

var/spack/repos/builtin/packages/gettext/package.py

@@ -49,7 +49,6 @@ class Gettext(Package):
     depends_on('libxml2',  when='+libxml2')
     # Java runtime and compiler (e.g. GNU gcj or kaffe)
     # C# runtime and compiler (e.g. pnet or mono)
-    depends_on('git@1.6:', when='+git')
     depends_on('tar',      when='+tar')
     # depends_on('gzip',     when='+gzip')
     depends_on('bzip2',    when='+bzip2')
@@ -86,9 +85,6 @@ def install(self, spec, prefix):
         else:
             config_args.append('--with-included-libxml')
 
-        if '+git' not in spec:
-            config_args.append('--without-git')
-
         if '+bzip2' not in spec:
             config_args.append('--without-bzip2')