convert: delete empty directories if deleting a file (bug 754)

bdiff: switch to lyhash lyhash is a very simple and fast hash function that had the fewest hash collisions on a 3.9M line text corpus and 190k line binary corpus and should have significantly fewer collisions than the current hash function.

bdiff: use INT_MAX to avoid some inner loop comparisons

bdiff: simple splitlines optimization

I have spotted the biggest bottleneck in "bdiff.c". Actually it was pretty easy to find after I recompiled the python interpreter and mercurial for profiling. In "bdiff.c" function "equatelines" allocates the minimum hash table size, which can lead to tons of collisions. I introduced an "overcommit" factor of 16, this is, I allocate 16 times more memory than the minimum value. Overcommiting 128 times does not improve the performance over the 16-times case.

revlog: fix revlogio.packentry corner case We want to store version information about the revlog in the first entry of its index. The code in packentry was using some heuristics to detect whether this was the first entry, but these heuristics could fail in some cases (e.g. rev 0 was empty; rev 1 descends directly from the nullid and is stored as a delta). We now give the revision number to packentry to avoid heuristics.

Don't try to determine interactivity if ui() called with interactive=False. WSGI applications are not supposed to refer to sys.stdin. In ed6df6b1c29a, hgweb and hgwebdir were fixed to pass interactive=False to their ui()'s, but sys.stdin.isatty() was still called by the ui objects. This change makes sure only the ui.fixconfig() method will call ui.isatty() (by making the ui._readline() method, which is currently only called from ui.prompt(), private). ui.fixconfig() is changed to let config files override the initial interactivity setting, but not check isatty() if interactive=False was specified in the creation of the ui.

Merge with crew-stable

convert_git: avoid returning two entries for the same file in getchanges This could happen in merge changesets if the merged file was different from both parents.

mq: fix qrefresh -e with no patches applied