Merge branch 'release/v0.2.1' into develop

* release/v0.2.1:
  bump version to 0.2.1
fixes for stricter warnings
switched on and fixed a bunch of warnings
bump to v0.2.2
Merge branch 'release/v0.2.2'

* release/v0.2.2:
  bump to v0.2.2
  switched on and fixed a bunch of warnings
  fixes for stricter warnings