Dropped Python2 support; bugfixes

Cleanup

* removed all u"..." strings and other Python2 related code
* run flake8 checks; considerable reformatting
* version bump: v0.6.0.dev2

Segmentation details dropped

Fixed in this release

Handling of configs and advanced annotation features

• Persistent configurations implemented (sff config [list|get|set|del|clear])
• Restructuring of documentation (more to come)
• Better handling of AmiraMesh files
• Annotation features: copying notes (sff copy [options]); clearing notes (sff clear [options]); searching notes in EMDB, PDB, UniProt in addition to EBI-OLS with much neater tabulation of search results; --details <details> now working
• h5py version restricted to 2.6 because of breaking changes in newer versions

Other:

• CI with Travis and Gitlab-CI

Now including global external references

v0.1.1.dev0

updated documentation