Overhaul implicit conversion of arguments and return values * oct-py-types.cc, oct-py-types.h (pytave::py_implicitly_convert_argument, pytave::py_implicitly_convert_return_value): New functions. * __py_struct_from_dict__.cc, oct-py-eval.cc, pycall.cc, pyeval.cc, pyexec.cc: Use them instead of legacy conversion functions. Add necessary #includes, remove #includes of legacy header files. * @pyobject/subsasgn.m, @pyobject/subsref.m: Change %!tests that depend on NumPy implicit conversion into %!xtests. * octave_to_python.cc, octave_to_python.h, python_to_octave.cc, python_to_octave.h: Delete, no longer used. * Makefile.am (COMMON_SOURCE_FILES, PYTAVE_HEADER_FILES): Remove the files.

--- a/@pyobject/subsref.m	Tue May 02 17:40:01 2017 -0700
+++ b/@pyobject/subsref.m	Wed May 03 16:30:45 2017 -0700
@@ -152,7 +152,8 @@
 %! assert (b, 2)
 %! assert (char (c), "Octave")
 
-%!test
+## Test that depends on implicit creation of NumPy arrays, do we want this?
+%!xtest
 %! % 2D array indexing
 %! A = pyobject ([1. 2.; 3. 4.]);
 %! assert (A{1, 1}, 1)