Fix for deprecated warnings when compiling

The BytesWritable class deprecated the get() and and getSize() methods
since r0.19.2. Updated to use new getBytes and getLength methods.
http://hadoop.apache.org/common/docs/r0.19.2/jdiff/changes/org.apache.ha
doop.io.BytesWritable.html
Merge pull request #7 from brownsys/bytesWritable-fix

Fix for deprecated warnings when compiling
properly size minimum input size so it fits within 64 MB block

thanks to zhuozhl@g.clemson.edu for the bug report
Merge pull request #9 from brownsys/minSizeFix

properly size minimum input size so it fits within 64 MB block