Move most GeanyApp fields into:
GeanyPrefs for (most) Preferences dialog fields;
UIPrefs for non-Prefs dialog visual settings;
UIWidgets for less commonly used widgets such as menuitems and
dialogs;
GeanyStatus for various states the application can be in.
Move some GeanyApp fields into EditorPrefs (and one into each of
CommandLineOptions and SidebarTreeviews).
Add plugin API prefs field.
Move disabling build widgets on Windows to build_init().
Make build callbacks static.
Add treeviews_init() to prepare popup menus and open files treeview.
Replace treeviews_find_node() with treeviews_select_openfiles_item().
Make utils_isbrace() and utils_is_opening_brace() take an
'include_angles' argument (to separate from editor_prefs).
Make 'Goto matching brace' keybinding include <> angle brackets.
git-svn-id: https://geany.svn.sourceforge.net/svnroot/geany/trunk@1815 ea778897-0a13-0410-b9d1-a72fbfd435f5
