[PATCH 0 of 7] parentdelta patches ready for testing

[in3xes at gmail.com]

Hi,

   These patches are ready for testing. To test them simply import all the patches except last one to queue and enable parentdelta format and set path to the compress extension in configuration file

Ex:
[format]
parentdelta = True

[extensions]
compress = /path/to/compress.py

Now efficiency is pretty good compared to previous version. On my machine efficiency has decreased to 1.3x for new repo and less then 1.1x for older repos. 7th patch is to find minimal delta among prev, p1, p2. The current approach is  expensive compared to memory efficincy.

Test results.

Mercurial repo manifest 10Mb to 2Mb
Mozilla repo manifest 53Mb to 25Mb