gainsag: need to write a new module to create new gsagtab due to #2

[cmagness]

due to the database error(s) in #2, need to write a new module that will update last delivered gsagtab with new gainsag holes from gainmaps

[cmagness]

still need to:

• [x] add a function for plotting gain regions discovered (and maybe by date of when they appeared? -- enhancement)

• [x] finish function for updating previously delivered table

• [x] add a function for updating header related information on file (like history, etc.)

• [ ] does a function need to be added for testing for pipeline/crds compatibility or should that be separate? no, james has technical testing tools

• [ ] add support for LP positions so that it is independent

• [ ] add a class to handle all the floating bits like hv_level, segment, LP, etc.

• [ ] there was something else option wise i wanted to added (something about dates to search? blue vs not reference file? idk will update if i remember