Merge pull request #22 from timeoverflow/translations

Translations
Update README.md
Update README.md
One bugfix (@tag_list) and layout improvements on offer index
Id number is required for User
Sort users by reg number (re: #20)
Default regisgtration date for user is today. Re: #20
Summer work. Who knows what happened?
Gem cleanup.
Added persona and devise as external libs
Updates for bootstrap 3.
Icons, turbolinks and some more layout things.
Bootswatch theme. Some fixes
Added configurable theme for org.
Helperized the theme stylesheet tag.
Translations
Added rspec. WTH, everyone loves rspec!
Añadida traducción para categoría.

Para añadir o cambiar una traducción en n idioma concreto
hay que usar la consola, o (cuando esté) la pantalla
de gestión de categorías, con la aplicación en el idioma deseado.
Added gravatar for users. Display in menubar and user list.
Fix account update balance loop