- single function to create kernel for specified target
- data type creation from string - reuse numpy functionality
- bugfixes in dot display

- renaming because of clashes with types.py from other packages

and not as a string.
Changed name of the file TypedSymbol to types.
Fixed usage of dtype accordingly, however i might not have found every
usage of dtype.

- LoopOverDomain changed to be able to loop over rectangular sub-region of field
- support for slicing with makeSlice

- added sphinx files for documentation generation
- collected kernel creation functions in new "cpu" and "cudagpu" modules