Merged changes from trunk

* r3379: gribapiDefLevel: use function grib2DefLevel() to write grib2 levels
* r3370: vlistMerge: compare size of grids (bug fix)
* r3369: gribapiScanTimestep1: fixed bug from previous merge of branches/cdi_fileDrivenInput (GRIB2 read failed)
* r3368: include config.h
* r3363: merged changes from branches/cdi_fileDrivenInput