mercurial: Update mercurial to 3.0.1

Update the mercurial version to 3.0.1.
Update the checksums.
Remove the PR per current best-practice.

This resolves an issue with Mercurial 1.9 where fetching from behind a
proxy breaks with a python stack trace. The current python
httpconnection class no longer has the port setter method.

Signed-off-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>