Add test for exceeding filesize while calculating number of frames
Add test for exceeding filesize while calculating number of frames

This is an awful workaround, just to enable listening to files at all.
The way number of frames is calculated needs to be revised, as well,
as proper decoding of modes and frame types needs to be added.

Closes #2.

unjello/foo_input_amr,unjello/foo_input_amr,unjello/foo_input_amr