read version information from META-INF
Changed two utility classes to public

AvroSchemaConverter
CodecFactory
Rolled back one of the public classes
Merge pull request #46 from laserson/public_utils

Changed `AvroSchemaConverter` to `public`
add maven-jar-plugin version
Merge branch 'master' into version
add library version to metadata
Update README.md
Merge pull request #49 from Parquet/version

add Version in footer
reduce rep and def level buffer size. 8MB * 2 * #cols is way too much
Merge pull request #50 from Parquet/scale_down_overly_enthusiastic_buffer_size

reduce rep and def level buffer size. 8MB * 2 * #cols is way too much