merge with stable

outgoing: fix possible filtering crash in outgoing (issue3814) If there is no outgoiing changesets but we have filtered revision in outgoing.excluded We run into a filtering related crash. The excluded revision should not be there in the first place but discovery need cleanup in default, not stable.

test: display used python hash seed We keep using a random seed for each run, but we "compute" it ourself to be able to reproduce a failed test run.

outgoing: fix possible filtering crash in outgoing (issue3814) If there is no outgoiing changesets but we have filtered revision in outgoing.excluded We run into a filtering related crash. The excluded revision should not be there in the first place but discovery need cleanup in default, not stable.

parsedate: understand "now" as a shortcut for the current time

export: clobber files with -o (bc) (issue3652) This violated user expectation. Updated the code to clobber files, but preserve the behavior of appending multiple patches requested in a single export. Includes tests.

merge: don't call copies.mergecopies unless we need to This reduces the amount of time we spend calculating when doing a clean non-merge update. In a large repo, the time dropped from 10.1 seconds to 3.4.

merge: rename p1 to wctx in manifestmerge This is always a workingctx, and this name is more in line with other functions in this module.

largefiles: fix test and check code

histedit: always abort with same message when working dir is wrong. Using only one message makes live easier for translators. The clearer error message was supposed by Augie Fackler.