Various modifications:
- Remap more read types
- Gather featureCounts results for further processing
- Extra chromosome sizes read from config
- Avoid impossible fold heatmaps

This is so that the small RNA annotation script does not miss mCherry.

One out of seven UTR annotation from Ensembl (as distributed by illumina
Genome) do not match an end of the corresponding transcript.

Also avoid empty legend.

It seems that lfc_lfc scatterplots now lost the grey background and have
larger points. These unvoluntary changes could have been introduced when
trying to increase the axis label font size, or earlier.

Large unreadable figures.

Still a lot of work to do.

This will enable more flexibility to specify groups of libraries to be
plotted on one figure. This is currently used by metagene profiles.

Also introduced minor modification recently made for other pipelines.

Also did a little code cleaning and added a gene list to the small RNA
pipeline.

Rasterizing might make pdfs lighter.

Escaping underscore for tex-compatibility is now idempotent.

Also added a missing tex-compatibility escaping.

Also removed some debugging output that was written in a unique file in
/tmp, which prevented the small RNA annotation to be performed by a new
user without erasing this file.

The desired normalizer for bigwig files was not actually used.

Currently only the folds computed by DESeq2 are available for RNA-seq.

Now using `plt.gca().set_aspect('equal', adjustable='box')`.
See <https://stackoverflow.com/a/17996099/1878788>

Now using `plt.gca().set_aspect('equal', adjustable='box')`.
See <https://stackoverflow.com/a/17996099/1878788>