types and method declaration for sane_get_devices
basic open/close for device handles
get_option_descriptor and necessary types
deal with ownership of return values and out params
control_option and associated types
get_parameters and associated types
start, read, and associated type
actually, the maxlen parameter is the size of the buffer
cancel and set_io_mode
get_select_fd()
strstatus
some changes to get a test app to compile
pkg-config has sane-backends, so make this match
Make getting devices work.
Add a test application that can detect devices.
ignore by products of test app compilation.
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