swith to ragg for png outputs

Added more testing, a test coverage badge, and switched to ragg for png outputs from Cairo.

NSE fixes

v0.200.8

fixe to NSE filtering

Improvements and fixes

Various improvements and fixes in various places. See release notes.

gsea

Added ability to calculate enrichments using gene-set-enrichment-analysis (GSEA)

fixed bug in graph generation

• fixed a bug in the graph generation when nothing was significant (#41 )
• fixed various notes from R CMD check

version used in Emma Adams' thesis work

This is the version of the code used directly in Emma Adams' thesis analysis