Blueprint scopes

[Argmaster]

This pull request adds --scope/-s flag to simplify specifying where blueprint should be placed. Currently placing blueprint in assets/cubyz/blueprints/ requires either manual action or tricks with relative paths. After that change to save blueprint in assets/cubyz/blueprints all you have to do is include -s game and blueprint will be placed in mentioned directory on server side. To download blueprint you can use -s local, then blueprint will be placed in local ./blueprints/ directory.
On top of that this PR changes how locations of blueprints are specified. Now instead of raw path user should specify ID of blueprint.

Example:

/blueprint save -s game cubyz:stem will save clipboard to ./assets/cubyz/blueprints/stem.blp i.e. exactly in place where sbb system will look for it.
/blueprint list -s game will list all blueprints in assets (in form of IDs)
/blueprint save argmaster:stone -s world will save clipboard in ./saves/{current}/assets/argmaster/blueprints/stone.blp

Resolves: #1341
Related to: #1263

[Argmaster]

This will be handled by #1581, we could consider adding separate /blueprint download command to allow downloading server side blueprints to client. Blueprints should still be changed to use IDs instead of paths, but this can be done after #1425 so It doesn't require manually crafted parser.