Refactor Session error handling
Merge pull request #1109 from excilys/session-refactoring

Refactor Session error handling
Upgrade Logback 1.0.12, close #1111
Refactor loops so that condition can be evaluated asap, close #1105
Merge pull request #1113 from excilys/loops-refactoring

Refactor loops so that condition can be evaluated asap, close #1105