small fixes for test-newbranch
- hg tip doesn't use the branch cache; use hg log -r in its place
- commit doesn't use a HG_MERGE environment variable
- change the dates from "0 0" to "1000000 0"
changeset: 0:9c2cf2b35aa7
user: test
date: Mon Jan 12 13:46:40 1970 +0000
summary: add foo
changeset: 1:3756a9556b89
tag: tip
user: test
date: Mon Jan 12 13:46:41 1970 +0000
summary: change foo
2 revisions:
9c2cf2b35aa7
3756a9556b89