Fix line indentation.

The last lines was indented with tabs instead of white spaces.
Add desktop file to program.

I have added a .desktop file and I have configure
autotools files to install it correctly.
Implement gettext autotools support to the project.

There was a po folder created but there was no po files
and the autotools rules were not right configurated.
I have add two languages (Galician and Spanish) support creating
the po files and adding these langues to LINGUAS file. A rule to update
po files has been written in the Makefile.am file too.
Remove config.h.in file that was useless.

I have modify configure.ac file to generate this file.