Remove unused config.rpath from the toplevel Makefile.am

Signed-off-by: Víctor Enríquez <victor.quicksilver@gmail.com>
Add AM_GNU_GETTEXT_VERSION(0.19) to configure.ac

Signed-off-by: Víctor Enríquez <victor.quicksilver@gmail.com>
Remove the creation of config.rpath, ensure that the m4 folder is
created, fix error message.

Signed-off-by: Víctor Enríquez <victor.quicksilver@gmail.com>
Update POT creation dat in es.po and en.po.

Signed-off-by: Víctor Enríquez <victor.quicksilver@gmail.com>