Better bfabric-cli api read command

[leoschwarz]

This improves the command in several ways:

• Removes the automatic output type
• Multiple values can be submitted for the same key
• The query will be printed as a line of bfabricPy code
• --file parameter to write the output to a specific file
• Argument parsing is handled with pydantic now
• Added tsv support

[leoschwarz]

@CodingKaiser I've went ahead and added what we discussed and some more to the bfabric-cli api read command, cleaning up some of the problems that I wanted to change anyways.

The remaining thing which is not handled consistently is when nested values get flattened. Right now it's never except when you export a .tsv.

Otherwise, what remains is to add some tests.