Rename ICEsat2_SI_tools Module to tools for PEP 8 Compliance

[cpaniaguam]

This PR addresses the renaming of the ICEsat2_SI_tools module to tools in order to comply with PEP 8 naming conventions. PEP 8 recommends module names to be short, lowercase, and avoid underscores if possible.

Changes

• Renamed ICEsat2_SI_tools module to tools
• Updated all import statements and references to use the new module name

Files updated

Files in the old ICEsat2_SI_tools directory and relevant files in the analysis_db directory.

src/icesat2_tracks/analysis_db/A02c_IOWAGA_thredds_prior.py
src/icesat2_tracks/analysis_db/B01_SL_load_single_file.py
src/icesat2_tracks/analysis_db/B02_make_spectra_gFT.py
src/icesat2_tracks/analysis_db/B03_plot_spectra_ov.py
src/icesat2_tracks/analysis_db/B04_angle.py
src/icesat2_tracks/analysis_db/B05_define_angle.py
src/icesat2_tracks/analysis_db/B06_correct_separate_var.py
src/icesat2_tracks/tools/__init__.py
src/icesat2_tracks/tools/angle_optimizer.py
src/icesat2_tracks/tools/beam_stats.py
src/icesat2_tracks/tools/convert_GPS_time.py
src/icesat2_tracks/tools/convert_julian.py
src/icesat2_tracks/tools/filter_regrid.py
src/icesat2_tracks/tools/generalized_FT.py
src/icesat2_tracks/tools/iotools.py
src/icesat2_tracks/tools/lanczos.py
src/icesat2_tracks/tools/read_ground_tracks.py
src/icesat2_tracks/tools/sliderule_converter_tools.py
src/icesat2_tracks/tools/spectral_estimates.py
src/icesat2_tracks/tools/spicke_remover.py
src/icesat2_tracks/tools/wave_tools.py

[kmilo9999]

Can we merge this PR after #132 ?
That one has some changes in those files's code.

[hollandjg]

Looks good to me!

[cpaniaguam]

Can we merge this PR after #132 ? That one has some changes in those files's code.

Surely!

[hollandjg]

Great!

[cpaniaguam]

Completed in #189