update the changelog for 0.7.2
syntax tweaks
tweak README syntax
Getting rid of PyCharm config files.  Closes #52.
Merge pull request #64 from esc/changelog_0.7.2

update the changelog for 0.7.2
list items in the changelog to end with a period
fix syntax in ANNOUNCEMENT
tweak the release notes
fix syntax in RELEASING instructions
update ANNOUNCE.rst to describe version 0.7.2
bcolz 0.7.2