Fix deprecated grunt-contrib-livereload warning
Fix deprecated grunt-contrib-livereload warning

npm WARN deprecated grunt-contrib-livereload@0.1.2: Deprecated in favor
of grunt-contrib-watch which now have Livereload support built-in.

Change-Id: I7a14ad2c86719cf766f46ecdaa1ceb84203805d0
Signed-off-by: Thanh Ha <09ea4d3a79c8bee41a16519f6a431f6bc0fd8d6f@linuxfoundation.org>

opendaylight/dlux,stshtina/ODL,inocybe/odl-dlux,pinaxia/dlux,inocybe/odl-dlux,pinaxia/dlux,inocybe/odl-dlux,pinaxia/dlux,stshtina/ODL,opendaylight/dlux,opendaylight/dlux,stshtina/ODL