Quiet down exceptions at startup, and during tests

There's no need to display a traceback for every failed content load,
the comment before the log line even says so.

The exceptions shown before tests are run are because of the eager
initialization of the modulestores.  They don't need to be initialized
then, that just speeds the responsiveness of servers.  Putting off the
initialization means they get inited as needed, and the log lines get
No need to invoke classmethods through self.__class__
Word-wrap CHANGELOG.
Change css locator for Course Outline page in acceptance test
Merge pull request #1212 from edx/ned/word-wrap-changelog

Word-wrap CHANGELOG.
Merge pull request #1194 from edx/ned/quiet-tests

Quiet down exceptions at startup, and during tests
Merge pull request #1213 from edx/zoldak/fix-broken-acceptance

Change css locator for Course Outline page in acceptance test
Studio: adds JS/functionality dependent class to course updates <body> elem
Studio: adds in older styling dependent class to unit <body> elem
Merge pull request #1214 from edx/talbs/fix-studio-bodyclasses

Studio: Fix - HTML <body> class regressions
Merge pull request #1198 from edx/ned/fix-calling-classmethods

No need to invoke classmethods through self.__class__
Switch get_html replacement out for using wrap_child