Add test to check if config setting is correctly retrieved

add a bit more assertation description on test
Add domain id to cachestring
multipledomain config get working

fix setting test to only call create if required
minor fix on setting test where error exposed by fixes elsewhere
fix failing settings test by allowing more cache clearing
interim commit setting test passing but regression on api test
updated version of examples
really finally working
Merge pull request #401 from eileenmcnaughton/settingtestnew

 CRM-12330 - Caching bugs in api setting code