tags: improve documentation
The documentation for tags.py was making comprehension difficult.
This patch rewrites most of the comments in the file to make it easier
for mere mortals to understand what's going on.
phase: compute phases in C
Previously, the phase computation would grow much slower as the oldest draft
commit in the repository grew older (which is very common in repos with evolve
on) and the number of commits increase.
By rewriting the computation in C we can speed it up from 700ms to 7ms on
a large repository whose oldest draft commit is a year old.
clone: add progress support to hardlink clones (
issue3059)