Pymusiclooper

- Partial code re-organization and improvement; better exception handling

- Merged the 'complete' installation option with the 'core' installation

- CLI can now be launched directly by calling `pymusiclooper` in the terminal

V2.0 Rationale: This release marks a milestone in stability over the v1.x versions, rather than a major update. Future major releases will be reserved for large changes in the code base (e.g. overhaul of the core algorithm), or breaking changes in API/shell commands.

- Removed --json export option in favor of the more versatile--txt option
- Performance improvements to beat comparisons as a result of using native numpy functions whenever possible
- Code refactoring and streamlining of internal functions

- Added a --txt option to export a loop.txt file compatible with LoopingAudioConverter
- Recursive batch export now replicates the source directory tree structure by default to avoid name conflicts
- Added a --flatten option for recursive batch export to output to a single folder without replicating the source directory structure (previous behaviour)
- Lowered note similarity threshold to improve loop point quality (from 10% to 8%)
- Renamed default output directory name from looper_output to Loops
- Fixed JSON export bug
- Fixed a bug with non-recursive batch export.

- Added -i/--interactive feature to CLI for manual loop previewing and selection
- Fixed an issue with the loop ranking algorithm triggering with lists having < 2 candidates