Renombra activity -> fragment

git-svn-id: https://tdam-2013-g5.googlecode.com/svn/trunk@228 0117bdac-9510-e2bd-253c-24df4fda417d
Refactor por renombre activity -> fragment

git-svn-id: https://tdam-2013-g5.googlecode.com/svn/trunk@229 0117bdac-9510-e2bd-253c-24df4fda417d