Fix for the Jira issue IOT-524

Fix for the Jira issue IOT-524

This patch addresses the first part of IOT-524. This patch is a continuation of
the changes submitted at https://gerrit.iotivity.org/gerrit/#/c/1439/.
The current changes include installing the public header files inside PREFIX/include/
directory.
For ex: /home/XYZ/BUILD_IOT_PREFIX/include/resource/ocstack.h

Change-Id: I40be9cfe112a81263fb22acf494fa7f8fd8dc549
Signed-off-by: Ravi Nanjundappa <nravi.n@samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/2362
Tested-by: jenkins-iotivity <jenkins-iotivity@opendaylight.org>
Reviewed-by: Jon A. Cruz <jonc@osg.samsung.com>