Add support for form 1120 family for Corporate income tax Modernized e-File

[Prosp3r]

Support for IRS Modernized e-File Forms 1120, 1120S, and 1120-F for Tax Year 2020 and beyond.
Our design goal is primarily to extend moov-irs in such a way that given JSON representation as input it produces Modernized e-File compliant files for transmission to the IRS.
Modernized e-File(MeF) Overview

The Modernized e-File(MeF) approved file transmission format is XML and as such moov-irs will produce files compliant with IRS Business rules and all xml schema specifications for (MeF) for the various families of form 1120 starting with 1120.
Updates will be made to keep the system up to date with changes in subsequently released instructions from the IRS.