Reorganize scripts into new package

[kelle]

• scripts moved to new package
• schema folder renamed schema

Link to relevant issue: Closes #456 and #372

[Will-Cooper]

minor thing to update import group order to be external libraries > standard libraries > local libraries, so plotting_example would become

from astrodbkit2.spectra import load_spectrum
import astropy.units as u
import matplotlib.pyplot as plt
import numpy as np
from sqlalchemy import and_, cast, func, Integer

import logging

from scripts.ingests.ingest_utils import convert_spt_code_to_string_to_code
from scripts.ingests.utils import load_simpledb, logger
from scripts.ingests.simple_utils import convert_spt_code_to_string_to_code

[kelle]

I appreciate this comment, but I don't think it's high priority to do that type of cleaning on the example scripts in this repo. The examples that end up in the template repo, on the other hand, should be as perfect as possible.