cmd/tsuru-base: add better test for previous jsonWriter bug

This tests would fail before d6b593f8bc8d06d8eac041faa252c7eef47843cb. I
should send it together with the jsonWriter change, sorry about that :-(
Added a new theme for tsuru docs.

Related to #385.
changed layout to theme.

Related to #385.
auth: move token related stuff to token.go file
auth: s/newToken/newUserToken/
db: add tokens collection

This collection will store all tokens. No more token embedding.
auth: move tokens to their own collection in the database
api: fix token related tests
docs/static: update date in Twitter copyright note
changed docs header.
docs: added style for paragraph.
docs: removed unused css.
docs: added a active class for 'documentation'.
docs: added bg.
auth: add function for application token generation

Related to #388.
auth: added CheckApplicationToken function

This function will check the whether a given token is valid.

Related to #388.
auth: don't mark user tokens as valid application tokens

Related to #388.
auth: implement json marshaling of tokens

Related to #388.
api: starting to build generateAppToken handler

Related to #388.
auth: validating the presence of the client key in the JSON body

Related to #388.