New annotation: @venus-fixture-reset (true|false)

You can now disable the behavior of reseting test HTML fixtures after each test executes.

To disable this behavior, use: `@venus-fixture-reset false`

If this annotation is not present, then the default value will be true.
Merge pull request #230 from sethmcl/disable_fixture_reset

New annotation: @venus-fixture-reset (true|false)