Version bump to 5.6.0dr1

This major version includes the new SWIMA IMC/IMV pair which
implements the "draft-ietf-sacm-nea-swima-patnc" Internet Draft.
Full compliance to the ISO 19770-2:2015 SWID tag standard has
been achieved.

testing/testing.conf

@@ -31,7 +31,7 @@ fi
 : ${KERNELPATCH=ha-4.4-abicompat.patch.bz2}
 
 # strongSwan version used in tests
-: ${SWANVERSION=5.5.3}
+: ${SWANVERSION=5.6.0dr1}
 
 # Build directory where the guest kernel and images will be built
 : ${BUILDDIR=$TESTDIR/build}