changed es/Leame.1st
upgraded the list of files on translation and revision.

added a term (builtin) to the glossary

changed es/concepts.tex
file added to define labels needed by other tex files

changed es/preface.tex
killed a TODO

changed es/tour-basic.tex
I have began the translation of this file. 34% completed, according to vim

changed es/undo.tex
file added to define labels needed by other tex files