doc: improve match pattern for manual page references with custom_see_handler.

* doc/doc.md: Use '[%w_]+' instead of '%a+' so that references
to, say, _exit(2) and dup2(2) work too.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
Fix minor issues with the "prettify" facility.
Merge pull request #130 from mooffie/fix_prettifier_last_lines

Fix minor issues with the "prettify" facility.
Add entries missing in rockspec.
Command-line flags that were explicitly passed by the user should take precedence over config file defaults.
Don't call function when missing. Tweak needed for ldoc to build its own documentation files.
Merge pull request #136 from hishamhm/master

Give command-line flags priority over the config file (plus minor fixes)
Fix issue #123: override 'boilerplate' was done too late
Merge pull request #138 from dirkfeytons/master

Fix issue #123: override 'boilerplate' was done too late
Being more direct on how tags look like when introducing them first
Rewrite of first introductory paragraph

A suggested rewrite of first introductory paragraph. It does drop some information (e.g. second generation) in favor of being more beginner's friendly and more basic in what this is actually about. The followup LDoc-referring paragraphs seem sufficient to cater the needs of advanced doc tool users, while the first paragraph possibly stumps and scares away beginners in its current form.
Getting all the sections in a more beginner's friendly, logical order
Some more reordering, introducing tags more explicitly
Fixing tag introduction example (hopefully?)
Better section naming, some hints for C code
Removing inconsistent header colon
Merge pull request #141 from JonasT/patch-2

Rewrite of first introductory paragraph
Merge pull request #142 from JonasT/patch-3

Major reordering and renaming of sections of documentation
Merge pull request #140 from JonasT/patch-1

Being more direct on how tags look like when introducing them first
more general method of controlling visibility of local functions or items marked with @local