Mavericks fix to APM_Toolbar

QTBUG 34300 causes relative path references to qml file loading to fail.
Merge pull request #422 from DonLakeFlyer/Mavericks_Fix

Mavericks fix to APM_Toolbar
Fix crash when acceptance in pixels == 0
Merge pull request #424 from DrTon/acceptance_fix

Fix crash when acceptance in pixels == 0
change type of port from uint16_t to quint16
Merge pull request #426 from thomasgubler/fix_type_compile_error

change type of port from uint16_t to quint16