add testfile dependency to python test

a bit of error handling for CdiInfo
no testdata dir anymore because it's only a single file

* rm Lib-interface
* unify filenames for config and test
* rm pre-build wrapper code - now SWIG is always needed

* use word-boundary
* avoid false types like int_64_t
* adopt the f2003 example for large integer for dates
* add autogenerated mo_cdo.f90

unsigned char <name>[]
const unsigned char <name>[]

* Since write, mmap and a number of other functions are not part of
  ISO C (i.e. strictly conforming programs must not use those), we need
  to ensure the build environment provides POSIX conformance.
* This mostly prevents unrelated bug reports later on.
* From POSIX 2008, CDI unconditionally only uses getline and has a
  work-around in case that is missing.

* Do not create unnecessary temporaries.

* The previous implementation was not thread safe (accidental SAVE
  attribute) and handled string arguments of full length without a
  c_null_char terminator incorrectly.