Oruga v0.8.X upgrade

[whiplashwebb]

This PR upgrades the Bulma Theme so it works with Oruga 0.8.X. All changes depend on Oruga PR #777.

Fixes: #92, #96

Proposed Changes

• Various config changes to deal with classes which can no longer be generated by the theme. Previously the classes used computed and/or data passed from Oruga to the theme. These values cannot be passed as of 0.8.0.
• Expanded dropdown position CSS to deal with the expanded range of options. Visually there should be no changes.
• Adds $dropdown-gap for easy control of the space between trigger and dropdown menu.
• Refactors steps scss to deal with breaking changes to structure.
• Refactors tooltip to look for variant/position classes on the content node rather than the root node.

[jtommy]

@whiplashwebb great job, for me it's ok