Lots of little fixes.

- merged CloseCompressor and CloseDecompressor into one function
- keep existing errors in error function (for exceptions raised in the
  Compress or Decompress callback functions)
- remove newline from error string generated by error function
- allocate less memory when compressing multiple frames
- keep existing errors when clCompress or clDecompress fails
- raise an exception when compressed data doesn't fit within
  dataMaxSize bytes
- allocate frameSize bytes for decompression buffer instead of
  dataMaxSize
- use mkvalue more often
- new function QueryParams which will accept CL.AUDIO and CL.VIDEO
  args
- changed some function names