Make salhelper testapi cppunit work
- removed call to simpleheader.hxx
- added call in Module_sal.mk for sal_testapi
- created mk for cppunittest for sal_testapi
- fixed some compile warning for auto_ptr

Change-Id: I07a58dbd5282f92604f58eb450e0bf549c54c6b3
Reviewed-on: https://gerrit.libreoffice.org/839Reviewed-by: Muthu Subramanian K <muthusuba@gmail.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>