evolve: add an `--update` flag to `hg evolve` command This patch adds a new `--update` flag which defaults to True. The update flag updates the working directory to the head of evolved revisions after `hg evolve` command. This flag can be used to not update your working directory after `hg evolve` which has been one of the biggest feature request from fig team at Google. To not update your working directory, the user can do `hg evolve --no-update`. If the working directory get obsoleted by evolve command, it will update to the successor. This patch also adds some basic tests for the flag introduced.

all: tutorials/tutorial.rst tutorials/topic-tutorial.rst static/logo-evolve.ico
	sphinx-build . ../html/

tutorials/tutorial.rst: tutorials/tutorial.t test2rst.py
	python test2rst.py tutorials/

tutorials/topic-tutorial.rst: tutorials/topic-tutorial.t test2rst.py
	python test2rst.py tutorials/

static/logo-evolve.ico: static/logo-evolve.svg
	convert -resize 36x36 static/logo-evolve.svg static/logo-evolve.ico