SEADAS: Add PACE and NSIDC file reader

[knowles]

This adds the PACE (OCI, SpexONE, and HARP2) file readers and the NSIDC reader.

Note: this pull request is dependent on the snap-desktop and snap-engine pull requests for "SEADAS-angular-NSIDC-11.0.0-04-30-24": https://github.com/senbox-org/snap-desktop/pull/221 https://github.com/senbox-org/snap-engine/pull/443

Also Note: the branches in the snap-engine and snap-desktop were updated on May 7 to include logic which now only displays "View Angle" in the Properties GUI when it has been set (which currently is only for the PACE polarimeters).

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
0 out of 2 committers have signed the CLA.

:x: xuanyang02
:x: knowles
_{You have signed the CLA already but the status is still pending? Let us recheck it.}