Improve dragknife postprocessing

The dragknife plugin currently produces arcs that fail validation when
sent to grbl.

When the tangentialOffset method is called on an arc segment, both it's
start and end position are offset. The center is moved such that it is
equidistant between these new positions. This produces a valid arc.
However, when turned into GCode, only the center and end positions are
used - the start position is assumed to be the end position of the
previous command. This *isn't* a valid arc, and GCode processors like
grbl will report errors when sent this GCode.

This commit fixes the problem by using the end of the previous (tangentially
offset) segment as the start of subsequent offset arc segments.

pypi bump

warning

Compile to .exe vlachoudis#437

Merge pull request vlachoudis#664 from wolfmanjm/new-status-format

Modify status handling for new smoothie query format

- Added adaptive laser cutting option

- Recent menu, justified with directory entries

Increase the release number, especially for the probing bug on z

G90 in scan function

If the editor tab is not displayed all ".event_generate()"

messages are lost. So it is better to send them to winfo_toplevel() before
This solves an old bug that sometimes the canvas is not in sync with
the editor

New strings