[Denemo-devel] Version bump to 2.0.19

[Richard Shann]

I have just re-organized the Directives menu (mainly because the 1st&2nd
time bars were rather buried) and so have bumped the version number to
the next development version 2.0.19
The bump in the version number means that people following the
development versions won't have to re-import the commands to get them to
move to their new positions.

Richard