Pydra

- fixing copyfile input
- adding flexibility to position of the shell task fields
- Simplify output_spec definition and population
- Various adjustments to ShellCommandTask
- adding full traceback to the error files
- updating Ubuntu for CI
- fixing templates with float formatting and multiple fields
- fixing hashing function for numpy objects
- fixing __call__ function for Workflow
- adding container dimension concept to the `split` method
- adding `LazyField` for MultiInputFiles
- fixing issues with `SoftFileLock` with `asyncio`
- style and black updates
- fixing connections with multiple inputs

- reverting some changes to `hash_value` function, the part for arbitrary object didn't work well

- fixing `MultiInputObject` in the `input_spec`
- fixing numpy objects hashing
- small improvements to the `run` method for `Workflow` (moving some part to the softlock file block)

- changing the way of getting event loop with asyncio - more robust solution that should work even if `get_event_loop` raise an error
- adding option to specify a name of `Directory` using `output_file_template`

- fixing `TaskBase.__call__` so `submitter` is not overwritten
- improving `checksum_states` so it doesn't calculate the content hash of big files for multiple times (using `files_hash` that keeps track of all the files)
- removing output after task is run to save memory
- adding `Directory`, `int`, `float`, `bool`, `str`, and `list` to the types allowed by `output_spec` of `ShelloCommandTask`.
- adding python 3.9 to GA
- fixing GA singularity workflow

- removing `checksum` from `submitter` and `workers` to avoid hash calculation before running the tasks (using `uid` instead)
- saving the hash values for files to avoid content hash recalculation (the content is recalculated only if the time of the last modification has changed)
- adding `MultiInputFile` and `MultiOutputFile` to the pydra special types
- fixing environment variable for GithubAction CI
- fixing `input_spec` for `ShellCommandTask` with the `container_info`, spec `bases` has to be changed `DockerSpec` or `SingularitySpec` in order to be used by `Docker/SingularityTask`
- fixing automatic binding detections for `ContainerTask` that have files as input (`is_local_file` is now slightly more robust that work for input that has more complex type in the spec)
- expanding `callable` function used in field `metadata`, it can now use `output_dir`, entire `inputs` object or a specific `field` from the `inputs`