method to estimate base request size #263
expose data types on dimension objects #265

Added dimension sizes to the dictionary return. The mapping has
changed. Also need to add a dtype property to the VectorDimensions.
This required some modifications to the inheritance structure.

Closes #263.
Closes #265.
vector_wrap option causes mismatch between field and collection geometry #267

Moved some example files around and added a check to make sure the
geometry is correctly inserted into the collection. The issue occurs
when 0 to 360 longitudinal data is used and vector_wrap is True. Now
the geometry is appropriately copied in subset.

Closes #267.
handling of "point" spatial abstraction #214

Point abstraction is now used for operations even if overload and
bounds/polygons are available.
Merge branch 'master' into i238-icclim
mark - changed inheritance to allow for multivariate
mark - got the constructor working
mark - all tests working with DTR