Update 2.4.0

+ Improved dialog for synchronization with GPS files
+ GPS synchronization report
+ Improved track functionalety (improved presentation in tree view, waypoints, possibility to split tracks automatically when exceeding distance or time between two track coordinates etc.)
+ Proxy settings
* Updated French translation (many thanks to Arnaud Mouronval)
! Improved recognition of time zones and daylight saving time for GPS synchronization
! Several minor bug fixes