tklinuxcnc UI: rebranding
tklinuxcnc UI: rebranding

Get the LinuxCNC version number from the rebranded environment variable
(LINUXCNCVERSION), not the old one (EMC2VERSION).

Fixes #64.

Signed-off-by: Sebastian Kuzminsky <62d754cc350e84d3b1c32ae79f976f5348e74a40@highlab.com>

ikcalB/linuxcnc-mirror,ikcalB/linuxcnc-mirror,ikcalB/linuxcnc-mirror,ikcalB/linuxcnc-mirror,ikcalB/linuxcnc-mirror,ikcalB/linuxcnc-mirror,ikcalB/linuxcnc-mirror