Mustlink

Minor fix to (silently) drop columns in tables which expand to multiple parameters - e.g. telecommand parameters in a table of telecommands.

- Better exception handling
- Updated packaging for first release on pypi

No changes since v0.3 beta; any issues, please report them!

Additional API functions wrapped:
- `get_aggregations()`
- `tree_search()`

Additionally added `mode` & `fmt` keywords to `get_table_data()` in order to retrieve expanded table data (e.g. TCH with parameters)

This release includes a non-backward compatible change in the API:

`Must.search_description()` is now `Must.search_parameter()`

which takes a new parameter `search_by=` which can be `name` or the default `description`.