Version 0.11.0

In this release the python -m isal.igzip relatively slow decompression rate
has been improved in both speed and usability. Previously it was 19% slower
than igzip when used with the -d flag for decompressing, now it is
just 8% slower. Also some extra flags were added to make it easier to select
the output file.

• Prompt when an output file is overwritten with the python -m isal.igzip
  command line utility and provide the -f or --force flags to force
  overwriting.
• Added -o and --output flags to the python -m isal.igzip command
  line utility to allow the user to select the destination of the output file.
• Reverse a bug in the build system which caused some docstring and parameter
  information on igzip_lib and isal_zlib to disappear in the
  documentation and the REPL.
• Increase the buffer size for python -m isal.igzip so it is now closer
  to speeds reached with igzip.
• Add a READ_BUFFER_SIZE attribute to igzip which allows setting the
  amount of raw data that is read at once.
• Add an igzip_lib.IgzipDecompressor object which can decompress without
  using an unconsumed_tail and is therefore more efficient.