webos_certificates: Add bbclass to handle certificates

- Use it in ca-certificates

Open-webOS-DCO-1.0-Signed-off-by: Keith Derrick <keith.derrick@lge.com>
Open-webOS-DCO-1.0-Signed-off-by: Tapani Mattila <tapani.mattila@palm.com>

Change-Id: Ibe77162d9bd5afbc0b4768a441ef1b31bb2e361e
Reviewed-on: https://g2g.palm.com/1564
Reviewed-by: Tapani Mattila <tapani.mattila@palm.com>
Tested-by: Tapani Mattila <tapani.mattila@palm.com>
Reviewed-by: Ed Chejlava <ed.chejlava@lge.com>
Reviewed-by: Build Verification
Reviewed-by: Keith Derrick <keith.derrick@lge.com>
Reviewed-by: Susan Montooth <susan.montooth@lge.com>