Fixed a bug in the routines reading wind files. This has no effect on trajectories already run, it just prevents the model from crashing with some wind files. Fixed an array indexing bug which affects integrations with undefined parcels.
Parcels become undefined if they go off the top or the bottom of the model.
The bug means that integrations with undefined parcels from earlier versions of the model will have incorrect parcel paths. Multiple release of trajectories added. This allows several initial times to be used for trajectories release from the same initial positions. The time step is changed from 40 minutes to 30 minutes. This makes it easier to deal with the multiple release of trajectories.