Merged changes from trunk

* r3920: legendre.c: removed unused include
* r3919: added compare.h
* r3918: set revision number to 1.6.9rc1
* r3917: test/grid_search: update to YAC version 1.0.3
* r3916: clipping: update to YAC version 1.0.3
* r3915: Merge: Merge declaration and definition
* r3914: Vertintml: added default level
* r3913: ChangeLog: update
* r3912: fix typo
* r3911: Fldstat: added parameter noweights to use constant grid cell area weights
* r3910: change cdi svn:external to trunk/cdi (masked by local change)