Merge pull request #1 from sgomes/master

Updating calendar sample to use client_secrets and file_storage
Adding AdSense Management API sample
Minor fixes to new AdSense sample
Added support for caching discovered API
Various best practice fixes to samples:
- Switched to client secrets where appropriate
- Switched to installed application flow (google/api_client/auth/installed_app) where appropriate
- Added caching of API definitions where appropriate
- Added application name and version to client initialization
- Removed outdated OAuth Util (superceded by google/api_client/auth/installed_app)
Minor fixes
Merge pull request #2 from sgomes/adsense_sample

Adding AdSense Management API sample
Merge pull request #3 from sgomes/discovery_caching

Various best practice fixes to samples
Fix regex to match start of string instead of line