Allow to use markdown in yard docs and write better documentation for session's reset method
Add ability to save and open screenshot

This adds a new method `save_and_open_screenshot` that saves the screenshot then
opens it for inspection.

Refactor duplicate logic for `save_and_open_page` and `save_and_open_screenshot`
Merge pull request #1286 from abotalov/better_docs_for_reset

Allow to use markdown in yard docs and write better documentation for session's reset method
Only test base versions with 1.9.3

Doesn't seem to be a huge amount of gain in testing the base versions with multiple ruby versions currently
Merge pull request #1273 from gylaz/save-and-open-screenshot

Add ability to save and open screenshot