docs: various #12823

- increase python line-length limit from 88 => 100.
- gen_help_html: fix bug in "tag" case (tbl_count => tbl_contains)

ref #15632
fix #18215
fix #18479
fix #20527
fix #20532

Co-authored-by: Ben Weedon <ben@weedon.email>

src/clint.py

@@ -1,5 +1,7 @@
 #!/usr/bin/env python3
 #
+# https://github.com/cpplint/cpplint
+#
 # Copyright (c) 2009 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
@@ -29,15 +31,9 @@
 
 """Lints C files in the Neovim source tree.
 
-The goal of this script is to identify places in the code that *may*
-be in non-compliance with Neovim style.  It does not attempt to fix
-up these problems -- the point is to educate.  It does also not
-attempt to find all problems, or to ensure that everything it does
-find is legitimately a problem.
-
-In particular, we can get very confused by /* and // inside strings!
-We do a small hack, which is to ignore //'s with "'s after them on the
-same line, but it is far from perfect (in either direction).
+This can get very confused by /* and // inside strings! We do a small hack,
+which is to ignore //'s with "'s after them on the same line, but it is far
+from perfect (in either direction).
 """
 
 
@@ -61,25 +57,10 @@ Syntax: clint.py [--verbose=#] [--output=vs7] [--filter=-x,+y,...]
         <file> [file] ...
 
   The style guidelines this tries to follow are those in
-    http://neovim.io/develop/style-guide.xml
+    https://neovim.io/doc/user/dev_style.html#dev-style
 
-  Note: This is Google's cpplint.py modified for use with the Neovim project,
-  which follows the Google C++ coding convention except with the following
-  modifications:
-
-   * Function names are lower_case.
-   * Struct and enum names that are not typedef-ed are struct lower_case and
-     enum lower_case.
-   * The opening brace for functions appear on the next line.
-   * All control structures must always use braces.
-
-  Neovim is a C project. As a result, for .c and .h files, the following rules
-  are suppressed:
-
-   * [whitespace/braces] { should almost always be at the end of the previous
-     line
-   * [build/include] Include the directory when naming .h files
-   * [runtime/int] Use int16_t/int64_t/etc, rather than the C type.
+  Note: This is Google's https://github.com/cpplint/cpplint modified for use
+  with the Neovim project.
 
   Every problem is given a confidence score from 1-5, with 5 meaning we are
   certain of the problem, and 1 meaning it could be a legitimate construct.