update USAGE with python3
added upstream git link, so one can find source easily in future.
updated report as per script updates by Mike and new UTF-8 file
Add gen-unicode-ctype.py, rewrite of gen-unicode-ctype.c

This version produces *exactly* the same output as the C program:

$ gcc -o gen-unicode-ctype gen-unicode-ctype.c
$ ./gen-unicode-ctype UnicodeData.txt 7.0.0
$ ./gen-unicode-ctype.py -u UnicodeData.txt -o unicode-new --unicode_version 7.0.0
$ diff -u unicode unicode-new
$
Add parsing of DerivedCoreProperties.txt file
Use DerivedCoreProperties.txt as well for is_alpha(), is_lower(), and is_upper()

Do not only use the category 'Alphabetic' for is_alpha(),
also considier all non-ASCII digits as alphabetic.
ISO C 99 forbids us to have them in category “digit”,
but we want iswalnum to return true on them.
Add some comments to the LC_CTYPE output
Change the order of some character classes in LC_CTYPE output

(To keep the same order as in the current i18n file in glibc).
Also check whether character classes are added or omitted when generating LC_CTYPE