Release 0.5.19

Version 0.5.18

Belated tag for v 0.5.14 code

Release v0.5.13

Code for release 0.5.12

version 0.5.11 code

Merge of release-0.5.10 branch (which was the actual 0.5.10 release)

version 0.5.9, using master/ develop strategy