Revert "fixes for GFF3; going to branch to revert to GFF2 support"

This reverts commit 9e89346d430db6b535f09c42c28c50b823d0418b.
Revert "GFF3 work"

This reverts commit 4f465553c2ec8e017ec375cc7c6f123b9699a9ed.
Revert "GFF3 converstion work"

This reverts commit be6f6113838221bb8d77f71f5b6ee69ba6fab70c.
Revert all GFF3 work on GBrowse
* #910
* Note: remember to revert this commit when bringing in GFF3 changes to staging
Add full database paths for gff databases in GBrowse config
* #910 (sort of)
Add example landmarks for h_contortus_PRJEB506
Reinstate H contortus link
Merge
Keep all gff3 changes
* Reverted all the reverts... for easier merging back to staging (I hope)