updating sapos logo
styling sapos for the new logo

removing duplicated alert message (alert message is displayed above login form)

removing unnecessary sign_in message for login

changing login error message for users

removing old tiny frog gif and creating a small logo version

allow unauthenticated users to view credits

removing credits from footer

using new logo image as favicon image

UFF credits below content

updated SAPOS logo to a PNG with transparency

flattening top menu navbar

flattening login form
round borders only in the upper part of the main area
removing footer credits
Merge pull request #92 from tiagoamaro/logo_design_pull_request

Atualizar logo do SAPOS para a vencedora do concurso cultural