Clean the HTML manual upon 'maintainer-clean' rather than 'clean' in
case it was not built by Make but rather part of the distribution.
This is fine even then, as configure will properly require what is
needed to build it again if it is missing.
Don't set clean-local and all-local dependencies all together at the
end and rather let each section add the appropriate dependencies.
This makes each conditional more self-contained, and is safe as Make
allows adding extra dependencies to existing targets.
As it is generated by the build system it doesn't have to be checked
in, and having it in became a whole lot more annoying since it started
being generated automatically on `make all` instead of specific (and
weird) `make doc`, as it means whenever the documentation changes the
HTML is re-generated on any make run. This is particularly problematic
if using a different Docutils version than the one used to generate the
checked-in version as it would create local noise that should not be
committed, yet keep being annoying.
This situation probably leads to most people disabling (or at least,
not enabling) the documentation generation on normal builds, itself
leading to more hassle updating of the documentation.
FIXME: The `install-html-local` rule might be wrong since it's
copying `$(srcdir)/geany.html` instead of `$(builddir)/geany.html`
because for some reason generated `geany.html` is checked-in to
version control in the source `doc` directory.
I went through each link from the API docs and everything seems fine
since the extra leading whitespaces were removed in commits
`edaa6f713f1b8e037a56652da15032aac56e2227` and
`67ae7707364ecc09da8675803b48575d61b82fcf`.
At least the "Plugin Writing Guidelines" and "Plugin HowTo" sections
are displaying undesirable side effects of Markdown support, so disable
it at least for now.
Automatic config file update by running 'doxygen -u'. All previous settings are
kept but old, deprecated settings were removed to avoid annoying warnings
when executing doxygen (e.g. on the nightly cronjob to update the API docs
on geany.org).
Furthermore, the update tool added a lot of comments above the options,
which is probably good.
