It is really not needed as it does not add much value other then allows user to cast POJO function to its actual type. The reality is that the actual goald of POJO function is to make sure they can be looked at as plain Functions.
Resolves#514
rename fuction-sample-gcp to function-sample-gcp-http
refdoc polish
background sample polish
Resolves#525
Update pub/sub bg function to use base64 encoding
