Log message:
extend PYTHON_VERSIONS_ for Python 3.7

Log message:
Switch py-dateutils to plain DEPENDS.

It supports both python 2 and 3 nowadays.

Log message:
Add python-3.6 to incompatible versions.

Log message:
Remove python33: adapt all packages that refer to it.

Log message:
Extend PYTHON_VERSIONS_INCOMPATIBLE to 35

Log message:
Add SHA512 digests for distfiles for time category

Problems found with mismatching existing digests for:
	distfiles/asclock-classic-1.0.tar.gz
	distfiles/asclock-gtk-2.1.10beta.tar.gz
	distfiles/asclock-xlib-2.0.11.tar.gz
	distfiles/emiclock-2.0.2.tar.gz

Otherwise, existing SHA1 digests verified and found to be the same on
the machine holding the existing distfiles (morden).  All existing
SHA1 digests retained for now as an audit trail.

Log message:
Mark packages that are not ready for python-3.3 also not ready for 3.4,
until proven otherwise.

Log message:
Mark packages as not ready for python-3.x where applicable;
either because they themselves are not ready or because a
dependency isn't. This is annotated by
PYTHON_VERSIONS_INCOMPATIBLE=  33 # not yet ported as of x.y.z
or
PYTHON_VERSIONS_INCOMPATIBLE=  33 # py-foo, py-bar
respectively, please use the same style for other packages,
and check during updates.

Use versioned_dependencies.mk where applicable.
Use REPLACE_PYTHON instead of handcoded alternatives, where applicable.
Reorder Makefile sections into standard order, where applicable.

Remove PYTHON_VERSIONS_INCLUDE_3X lines since that will be default
with the next commit.

Whitespace cleanups and other nits corrected, where necessary.

Log message:
Convert to use versioned_dependencies.mk.

Log message:
Fixes:

 COMMENT should not be longer than 70 characters.
 COMMENT should not begin with 'A'.
 COMMENT should not begin with 'An'.
 COMMENT should not begin with 'a'.
 COMMENT should not end with a period.
 COMMENT should start with a capital letter.

pkglint warnings. Some files also got minor formatting, spelling, and style
corrections.