While the installation of the GTK runtime environment is optional,
we need the C runtime environment in every case and so install
it unconditionally.

Fix fuzzy entries in German translation

Update zh_CN translation

Fixes #1102.

updated it.po for upcoming 1.28

Properly expose TMTag which already contains documented members.

Don't use wildcards that can catch generated files.

While at it, also avoid Doxygen picking up those generated files.

This allows GI-based plugins to traverse/inspect the array and consequently
Geany loaded tags.

tm_tag.h and tm_parser.h contain documented symbols so doxygen shall process
them.

It's members are already documented so it's kind of half-exported anyway.
Since geanygendoc already uses the structure (and I plan on writing a plugin
that requires it too) just make it official.

Broken in #966.

Improve README

No behavioral changes.

Closes #1074.

X-Universal-CTags-Commit-ID: 91c6773373864da345a7a9e0f5bd01a25588471c

Fixes #756.