Preliminary support for an Ogg muxer

* BitStrings changed to resemble more of
Erlang bit syntax
* Update parsing SpeexHeader and SpeexComment
to use new Bitstrings
* Ogg muxer changed API to (de)mux instead (un)pack

TODO:
- need to fix granule position and checksum. for
 now they are always 0 which means that libogg
 fails to create the bitstream with invalid
 checksums.
Update app regarding the support for file encoding
Added some tests for ogg
Add CRC32 calculation for OGG
Fix null checksum in ogg muxer (for speexdec)

* Files encoded by speex.js are now working with
speexdec
Removed an unnecessary test.

* Was testing muxing the header with a precalculated
checksum and comparing against the original header page.
Ogg.mux now takes care of checksum so this test
doesn't make sense.
Update dist speex