Add URL handlers for links to remote projects and remote project files in Enterprise

[fuzyll]

What is the feature you'd like to have?
We have the ability to open binaries locally with binaryninja://<path> and a way to attach an Ultimate edition copy of Binary Ninja to an Enterprise server with binaryninja:enterprise://<server>, but we don't have a way to tell Binary Ninja to open a specific project or project file. We should. Something like binaryninja:enterprise://<server>/<project>/<file> might work? Unfortunately, not everything on the web understands/accepts these as valid URIs. So, we may want to consider some other alternatives as well.

Is your feature request related to a problem?
It would be very beneficial to a number of workflows to have a way to link to specific files. This would also be great for internal testing as well.

Additional Information:
This issue has been migrated from a different, internal issue tracker.

[galenbwill]

Tasks:

• Implement opening window in existing instance when no URL is provided
  • Add -n/--new-instance (or something) to force opening a new instance of binja
• binaryninja: URL handler in main.cpp needs to be able to dispatch based on nested scheme (currently only handles file: or http(s): because that's what Qt provides)
• Need a handler for enterprise: URL schemes that downloads from enterprise server

Extra Credit:

• Need a "copy location as URL" action, copies binaryninja:enterprise://server/project/file?expr=<address> to clipboard
• Should also be usable for local files and projects on any edition (except maybe Free?)