Added total_backed_projects to user_totals [Fix #54217720]

Now we count the total of backed project and not the total backs.
Move uservoice key to configuration[:uservoice_key] [Fix #54226220]
Use force_encoding on user.name on project received channel notification [Fix #54408738]

We need to find a better solution for this encoding problems.
solve slim incompatible warning
Merge branch 'master' of github.com:catarse/catarse into refactor_js