Methylartist

* tools for plotting C-U substitution data (WGBS, EM-seq)
* x and y limits for ridge plots (`segplot`)
* bugfixes

bugfix release due to packaging issues

Add features:
- [add --color_by_phase](https://github.com/adamewing/methylartist/commit/0ca27b3cd61eed2557d50cbb3a6b01651cd65ef2)
- [add --smoothed_csv option to output smoothed data to .csv](https://github.com/adamewing/methylartist/commit/5ce5b454cd187541d0a63378b73cf6b2ce18e733)
- [add --show_transcripts to locus/region](https://github.com/adamewing/methylartist/commit/04d7d3e4aaedef703879bd7121aa8dd9499c1a80)
- [add --exonheight to locus](https://github.com/adamewing/methylartist/commit/e8d420c111f622a3b527df7a53756e7f67d96839)


Notable bugfixes and updates:
- [fix modbam support for wgmeth when using --phased](https://github.com/adamewing/methylartist/commit/6ed7d98f14f2ac349713065d6329c5d48d4630b8)
- [handle cases where the read length is longer than the reference](https://github.com/adamewing/methylartist/commit/7b48512613eb054d49469ff5172be32134252108)
- [remove jitter keyword from violin plots](https://github.com/adamewing/methylartist/commit/6d6044e8aee225d30272b1bc20c3a09ce8d7bbd2)

- `region, locus`: change `--highlight_panels` to `--highlight_alpha`
- `region`: add gene-specific colours
- enforce `--motif` should only include IUPAC bases
- `region, locus`: custom colours if input is list of .bam files with two columns (2nd column being colours)
- add `-o`, `--outfile` as option to specify filename for tools with file output.
- various bugfixes

Fixes:
- skip bogus modified base data in .mod bams due to calls outside bounds of hard-clipped secondary/supplementary alignments
- `locus`/`region`: use "gene_id" if "gene_name" not in .gtf attributes
- various fixes to mod .bam handling, particularly around single base motifs

Features:
- `composite`: add --meanplot_cutoff, --output_table, --minelts, --maxelts options
- `locus`/`region`: add --plot_coverage option (experimental)
- depreciate `db-guppy`
- `scoredist`: support mod .bam

Bugfixes and feature requests:

- `locus`/`region`/`composite`: add `--ymin` and `--ymax` options to control vertical range on smoothed methylation plots (26)
- Try harder to detect .bam files if they don't have the .bam extenstion (25)
- `region`: Allow IUPAC codes for normalising region coverage (22)
- `wgmeth`: error instead of crash if `--phased` used on unphased data.