Remove hp timers from recon and gui

The high precision timers are not really needed on reconstruct or GUI any more, so allow them to be disable for a lower precision by no spinning version. This should save some CPU resources

added Performance label

changed the description

added Doing label and removed Performance label

mentioned in merge request !250 (merged)

closed via merge request !250 (merged)

mentioned in commit 6b2c12d9

mentioned in commit 0671b483