Add cimport-from-pyx to command line

Add FIXMEs to C-API functions that changed in Py3.7 but are not free of risk to adapt to because the error case returns ((unsigned long)-1) now instead of ((long)-1).

Disable yield-from integration test with asyncio in Py3.7 since asyncio Python coroutines are no longer iterable.

Closes #2111.

Re-enable method unpacking inside of the module init function if the call occurs inside of a loop (probably still worth it there).
See #2102.

Disable method unpacking inside of module init function by default as it really just increases the code size to uselessly speed up one-time code.
See #2102.

Closes #2106.

Do not compare the "writable_needed" flag when comparing memory views that condition is too strict and it is not currently used anyway.

implement read-only memoryviews

DOC: BUG: suggest install numpy debugging

or you get import error for `multiarray_d.so`

Repair memslice test after disabling auto-detection of read-only views, but keep some of the tests for 'const' views as smoke tests.

Disable auto-detection of read-only memory views (too unsafe) and acquire them only as read-only if the memory view dtype is a "const" type.

In Python 3, an unbound method is just a function

See #2102.

Specify license in cython-mode.el's header

Rewrite documentation paragraph on automatic string encoding for clarity