[Tizen][Runtime] Enable WGT CSP support.

The WGT CSP support is disabled by the PR#1593: Separate WGT
applications manifest handling from XPK applications. And this should be
enabled again by adding a CSP handler into the WGT manifest parser.
Merge pull request #1701 from takethathe/wgt_csp_handler

[Tizen][Runtime] Enable WGT CSP support.