Merge pull request #6 from alexeyvo/test

Implement connection pool
Added connection pool tests
Added connection pool tests
Changed from using mutex to use spinlock
Moved spin_lock to its own files
Added spin_lock class
Added spin_lock class
Removed custom spinlock logic and use new spin_lock.h
Small refactorings done
Merge pull request #7 from Convey-Compliance/service-bus-build

Small refactorings done
Merge pull request #8 from Convey-Compliance/master

Bring development up to date
Renamed done for destroy
Merge pull request #9 from Convey-Compliance/service-bus-build

Renamed done for destroy
Change malloc to bson_malloc, free to bson_free