Ensure DB8 libs and headers can be found by mojomail

* Link DB8 libraries from staging/lib to staging/usr/lib
* Copy mojodb header file folder from staging/usr/include to staging/include

Open-webOS-DCO-1.0-Signed-off-by: Roger Stringer <roger.stringer@palm.com>

Change-Id: Ief473cb50e7179157e7235d5515f2a8a8e7fd046
Reviewed-on: http://g2g.palm.com/1372
Reviewed-by: Build Verification
Reviewed-by: Roger Stringer <roger.stringer@palm.com>
Tested-by: Roger Stringer <roger.stringer@palm.com>