Add WebStatus authz "view" action.

This commit adds a new action to authz called "view". This action
represents the ability to view the Buildbot's WebStatus. If, for
example, you set `view='auth'` in authz, a user must be logged in to
view any meaningful status information.

The exception is that the root page and the login action are
whitelisted to always be viewable since these are necessary to log in.

Using this authz action it becomes possible to run a "private" Buildbot
instance for projects that don't wish to expose themselves to the
Internet at large.
Fixing popup in Console view in IE (verified against IE8)
Merge branch '2_view_action' of git://github.com/jimbru/buildbot
Merge branch 'BuildslaveDatabase' of git://github.com/jaredgrubb/buildbot
don't use assertIsNotNone, which doesn't exist in older pythons
sqlalchemy-0.7.10 seems fine, too
Merge branch 'console_ie_fix' of git://github.com/JustAMan/buildbot
db fixes for buildslaves improvements
Reason: allow 'reason' to be overriden in Schedulers and show in Builder page
Reason: update docs and release notes