tests/test-context.py

rebase: improve help text

- add a paragraph about default dest/source changesets
- option help: say "changeset" not "revision"
- option help: explain -b/--base better
- clarify that -a/--abort and -c/--continue are different from the
  other options

import os
from mercurial import hg, ui

u = ui.ui()

repo = hg.repository(u, 'test1', create=1)
os.chdir('test1')

# create 'foo' with fixed time stamp
f = open('foo', 'w')
f.write('foo\n')
f.close()
os.utime('foo', (1000, 1000))

# add+commit 'foo'
repo.add(['foo'])
repo.commit(text='commit1', date="0 0")

print "workingfilectx.date =", repo[None]['foo'].date()