Add validation to resource type/interface addition

Add validation to resource type/interface addition

The functions that add resource type/interfaces to the resources were
not correctly validating them to the RFC.  This commit adds validation
to these such that RFC6690 is enforced, and gives the developer
immediate/early warning of invalid values.

Change-Id: If04f72c1aa69ec2f9fbc83d849a503c2ee86f502
Signed-off-by: Erich Keane <erich.keane@intel.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/2605
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Patrick Lankswert <patrick.lankswert@intel.com>