Import spanish translation from transifex,  add Makefile

git-svn-id: http://svn.osgeo.org/postgis/trunk@13079 b70326c6-7e19-0410-871a-916f4a2858ee
Fix html tags in spanish translation

Classes of errors found:
 - Translated tags ( <command> to <comando> )
 - Missing angular brackets ( varname>x</varname> )
 - Invalid space in closing tag ( </ ulink> )

git-svn-id: http://svn.osgeo.org/postgis/trunk@13080 b70326c6-7e19-0410-871a-916f4a2858ee
Update spanish language files (make update-po), enable it

git-svn-id: http://svn.osgeo.org/postgis/trunk@13081 b70326c6-7e19-0410-871a-916f4a2858ee
Add hint about using --skip with tx push -t

git-svn-id: http://svn.osgeo.org/postgis/trunk@13082 b70326c6-7e19-0410-871a-916f4a2858ee