Fix tests to work with new TagBlock parsing format.

- These are the fixes to the tests that could not be fixed by altering the core parsing code base.
- Most involve adding TagBlock's, breaking out existing markup blocks and altering some AcceptedCharacter formats.
- Was able to loosen the restrictions on AcceptedCharacter's to allow the body of html tags to accept any character.

#75

These test fixes are here due to the changes in this PR: https://github.com/aspnet/Razor/pull/86
Would be very good to simplify / shorten use of this class.  As discussed offline, please add a constructor overload or two:
- single `string` parameter which is passed to `Factory.Markup()` or its functional equivalent
- same as above plus an `AcceptedCharacters` parameter which is passed to `.Accepts()` and overrides the `AcceptedCharacters.All` default

The first one is optional if you decide this (test-only) constructor should use a default parameter.