big refactoring which also introduces Elo model

* Only one nampespace is used (geography) instead of three
  previously used namespaces (core, accounts, questions).

* Redundant data from database has been removed or moved
  to special tables (skills and difficulties for Elo).

* A lot of things has been removed but should be added in the future
  (commands).

issues: #12, #13
post deploy hook for openshift
use geography application also in travis build script
turn off testing in travis build script since the MySQL is required
be more defensive when importing hashes
add lost commands
fix manipulation with users