Rename use of C++ `template` keyword in plugin API function argument
and add `G_BEGIN_DECLS` and `G_END_DECLS` to public header files to
make them easier to include in C++ code. TagManager and Scintilla
headers already have these `extern "C"` blocks so they shouldn't
require any modifications.
The Autotools build system already adds in a `dummy.cxx` to hint
Automake into C++ linking to support Scintilla, which is quite
convenient for dynamically loading of C++ plugins at run-time into
the otherwise C-only program. The other build systems seem to also
use the correct linking.
Change uses of lookup_widget() to ui_lookup_widget().
Remove now unneeded support.c.
Use GLib gettext macros in support.h instead of own ones.
git-svn-id: https://geany.svn.sourceforge.net/svnroot/geany/trunk@3402 ea778897-0a13-0410-b9d1-a72fbfd435f5
