Updating Simulator Java API project with the following changes.

Updating Simulator Java API project with the following changes.

1. Moved SimulatorResourceModel to the common package and renamed resource attribute class.
2. Added APIs for client controller
3. Added APIs for Observer information.
4. Updated Javadoc comments.

Change-Id: I6290d80557e309686b2fedb00332c209e53156fb
Signed-off-by: G S Senthil Kumar <senthil.gs@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/2353
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Madan Lanka <lanka.madan@samsung.com>