Second beta8 release

The first beta8 release included dependencies from the myget feeds which
weren't available at nuget.org. Removed the myget feeds and rebuilt.

Changes for beta8 release

Removed signing since EF7 itself isn't signed

Merge branch 'hotfix/3.0.3'

Merge branch 'hotfix/2.2.7' into support/2.x

[EF7] Update nuget

Merge branch 'hotfix/3.0.2'

Copy .teamcity from develop for building on the build server

Merge branch 'hotfix/3.0.1'

Merge branch 'release-3.0.0'

Fix connection close with open reader

We previously had an optimization whereby an open reader at connection close
time was closed asynchronously to return control to the user earlier. This
seems to be incompatible with ASP.NET, which doesn't allow async in
arbitrary places.

Removed the optimization, if an open reader exists when closing a connection,
it will be closed synchronously.

Also refactored and fixed closing behavior for non-pooled connectors.

Fixes npgsql#666

(cherry picked from commit 8bce3ca)