py3: remove superfluous indent from check-py3-compat.py

py3: make check-py3-compat.py load modules in standard manner Otherwise no code transformation would be applied to the modules which are imported only by imp.load_module(). This change means modules are imported from PYTHONPATH, not from the paths given by command arguments. This isn't always correct, but seems acceptable.

py3: include module filename in check-py3-compat.py output This change is intended to reduce noises in the next patch.

util: document we want Python type mapping to be temporary I think remapping Python C API types and functions is not a great approach. I'd prefer this whole #ifdef disappeared. Add a comment so we don't forget about it.

util: define PyInt_Type on Python 3 util.h attempts to wallpaper over C API differences between Python 2 and 3. This is not the correct approach where performance is critical. But it is good enough for the current state of the Python 3 port.

parsers: return NULL from PyInit_parsers on Python 3 This function must return a PyObject* or the compiler complains.

mail: take --encoding and HGENCODING into account Fall back to our encoding strategy for sending MIME text that's neither ASCII nor UTF-8.

template: provide a termwidth keyword (issue5395) We want to provide terminal-sized output. As a starting point, expose the terminal width to the templater for use in things like fill.

util: ensure forwarded attrs are set in globals() as sysstr Custom module importer strikes again.

pycompat: when setting attrs, ensure we use sysstr The custom module importer was making these bytes, so when we poked values into self.__dict__ we had bytes instead of unicode on py3 and it didn't work.