We subscribe to Sway's 'input' events, and use these to expose input
devices' active XKB layout.
The module is configured by specifying a list of 'identifiers'; these
are the input devices (keyboards, typically), that we'll be
monitoring. All other input devices are ignored.
'content' is a template, and the module will instantiate a dynlist
with a 'content' for each *existing* input found in the 'identifiers'
list.
We also monitor for device 'added' and 'removed' events, and update
our internal list of existing inputs.
This means the user can configure a set of identifiers, and only those
that are actually present will be displayed. If a device that is
listed in the 'identifiers' list is added, it will be displayed. If it
is removed, it will no longer be displayed.
Since this struct only contained function pointers, make all modules
export those functions directly.
The plugin manager now defines a module interface struct, and fills it
it by dlsym:ing the functions that used to be in module_info.
Since this struct only contained function pointers, make all particles
export those functions directly.
The plugin manager now defines a particle interface struct, and fills
it it by dlsym:ing the functions that used to be in particle_info.
Module plugins are (still) built in <build-dir>/modules.
When installing, f00bar binary is installed to <install-dir>/bin, and
the module plugins to <install-dir>/lib/f00bar.
For this to work, we now also set RPATH correctly. Since the installed
module plugins end up in a different location then when building,
different settings is required for BUILD_RPATH and INSTALL_RPATH.
