Created App Extension method Tests
Merge branch 'dev'
Using shared clientcontext in tests
Merge pull request #114 from erwinvanhunen/unittests

Unittests for app extension methods and some small fixes
Generic presentations on Office and SharePoint app topics. Useful slides to be used in with the app model related discussions.
Merge branch 'dev' of https://github.com/officedev/pnp into dev
Presentations for app model
Removed place holder
Created readme file for the presentations and documentation section.
Fixed some spelling mistakes