In some locales certain normal ASCII characters are not included in
the ranges [A-Z] and [a-z]. So, use [[:upper:]] and [[:lower:]]
instead, and [[:alpha:]] for [A-Za-z], and similarly for others.
This fixes https://savannah.gnu.org/bugs/?67094.
The names of the authors were retrieved from:
git log -p --follow syntax/<name>.nanorc
and from:
git log -p --follow --all -- doc/nanorc.sample
For some files the original author is unclear, or
the file is/was too small to mention an author for.
Adding "[abc]*" does not restrict the recognized header line in any way.
Also, improve the header-line regex for shell scripts, because it should
not match "barunscript" (for example).
Since file-5.10 (end of 2011), libmagic identifies a C file in most
cases as "C source" instead of as "C program". Nano's magic strings
for some other files didn't match any more what file-5.32 currently
produces, either. So, they have been adjusted, new ones added, and
old ones deleted.
This fixes https://savannah.gnu.org/bugs/?52445.
