Removed the &gt; entity replace in xmlrpc.inc

Changed addApp to return the added app.
Modified specific method definitions to allow an App specification to be passed in.
Added Methods to send an email template...  And to get a list of all contacts who have a tag in a specific category.
Merge branch 'master' of ssh://git@novaksolutions.repositoryhosting.com/novaksolutions/infusionsoft-php-sdk.git
Updated App Object so that we can do some testing... i.e. how many http calls were attempted, and so that we could set the timeout...
Added attempt count to Failure error message...
Update SmartCache to auto-generate the path if passed a relative path in __construct.
Update AppPool to clear all current connections (allows updating AppPool mid-request)
Update Contact with a method to check for the existence of a field.
Added Test Mock Stuff
Created More Testing Code
Invoice Service createBlankOrder, and addOrderItem work.