doc: fix grammar, spelling, punctuation
I restrained myself to making only changes that turn bad English into
good English. There are still opportunities to improve, but other
changes require some discussion and review. This change should be
uncontroversial.
recursive-include docs/figures *.svg
include docs/figures/hgview-example.png
include docs/*.rst
include docs/*.py
include docs/tutorials/*.t
include docs/makefile
include docs/static/*.svg
include hgext/__init__.py
include hgext/evolve.py
include setup.py
include README
include COPYING
include tests/*.t
include tests/*.py
exclude tests/test-oldconvert.t
exclude tests/test-qsync.t