changing the hdfs files to be C files
HDFS now uses CHPL_AUXIO_INCLUDE and CHPL_AUXIO_LIBS
Merge pull request #155 from tzakian/hdfs_env_variable_changes

Changing HDFS to use CHPL_AUXIO_INCLUDE and CHPL_AUXIO_LIBS for library and include paths. Updating README.hdfs to reflect this as well.
Merge pull request #154 from tzakian/hdfs_makefile_changes

Change HDFS files to C, and use a C compiler to compile them.