INFRA-14795: try to work out parent commit hash
INFRA-14795: try to work out parent commit hash

this should send a second commit line to multimail for
a hopeful diff. Also consolidate the 0x40 string a bit.

sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,sebbASF/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,apache/infrastructure-puppet,sebbASF/infrastructure-puppet,apache/infrastructure-puppet