New name, new browser, new version, new maintainer!

Just adopted this add-on - hoping to keep in maintained as needed in the future.

From here on out, I plan to only target Pale Moon. Because of this, the name has changed (BarTab Tycho), and I've bumped the major version number to 4.

The only real change with this release is allowing users to explicitly unload pinned tabs. This was previously disabled, and so I've just reverted that commit. I might move it into a configurable option though...

All versions of Pale Moon should be supported - Tycho was just a cool name!