Awsume

- Exports `AWS_REGION` and `AWS_DEFAULT_REGION` when using autoawsume

- Removes the dependency for `python-dateutil` which causes bugs with boto3's dependencies

- Fixes writing __name__ under each profile
- Fixes session expiration type as string when reading from cache
- Adds more logs

- Fixes line endings

- Fixes writing alias multiple times

- Refactored much of `awsumepy` and the plugin system to be more general and allow more types of plugins
- Utilizes callbacks and error catching better
- Adds custom exceptions
- Now combines credentials and config profiles under the same name
- Now merges source_profile credentials into their role profiles - everything you'll need is in the given profile
- Adds `--install-plugin` flag to download/install plugins from given urls
- Adds `--delete-plugin` flag to delete a plugin given the name
- Adds `--plugin-info` to display important information on currently-installed plugins
- Moved the `out_data` class into the AWSume app object
- New format for exporting data:
python
{
'AWSUME_FLAG' : 'Awsume',
'AWSUME_DATA' : [
'AWSUME_1',
'AWSUME_2',
'AWSUME_3',
'AWSUME_4',
'AWSUME_5'
]
}

- Adds `__exit_awsume` callback to stop a `^C` from spamming your terminal
- The `mfa_serial` of the source profile will be used if the role profile doesn't have an `mfa_serial`