Pass code as byte[] to Filter rather than an Enum pointing to the resource ID.

[bamos]

No description provided.

[bamos]

From @bgilbert in #28:

Since Filter is supposed to be generic, and only the caller will know what filters are actually available, FilterEnum and Filter.loadFilters() are problematic. It would be better to have the Filter constructor take a resource ID, and unpack the specified filter (and only that filter) itself.

Also, unpacking will need some work, because it shouldn't be done from the UI thread as it isnow.

[bamos]

I originally had the Enum wrapping res objects so the library could include
a default set of resources. The Enum was necessary because
applications using the library couldn't access the library's resources
directly.

I've removed the enum and the library's Filter class now loads the
resource ID from the application's resources.
I'm leaving this issue open for a binary constructor for Filter to be
added in the future.