refactor dictionary encoding
remove sorted strings encoding for now
rename encoding for consistency
Merge branch 'master' into refactor_dictionary_encoding

Conflicts:
	src/thrift/parquet.thrift
Merge pull request #75 from Parquet/refactor_dictionary_encoding

refactor dictionary encoding
fix plugin versions
fix plugin name
update mvn shade plugin instead
Merge pull request #77 from Parquet/fix_plugin_versions

fix plugin versions
Added sorted flag to dictionary page headers.
Merge pull request #78 from Parquet/sorted_dictionary

Added sorted flag to dictionary page headers.