Implement microlensing filter at the ANTARES broker

[rachel3834]

This task builds upon previous work by Somayeh Khakpash who has already written a filter for microlensing events in the ANTARES format. This is described in this notebook.

The next steps of development for this filter are to add features to compute parallax and other parameters to improve the classification and output parameter set, and to install it within the ANTARES system to make an operational alert feed.