meson.lang: Update to latest syntax
meson.lang: Update to latest syntax

- Update keywords and functions list
- Fix keyworks not being hightlighted
- Avoid matching built-in command if it's a method call, for example:
  obj.find_library()
- Avoid matching built-in command if not followed by parenthesis, for
  example include_directory in: library(..., include_directory : incdir)

GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview,GNOME/gtksourceview