PARQUET-105: use mvn shade plugin to create uber jar, support meta on a folder

1. Make hadoop dependency from parquet-tools so it is provided. It can be used against different version of hadoop
2. Use maven shade plugin to create a all in one jar, which can be used both locally or in hadoop
3. Make parquet-meta command support both folder(read summary file) and a single file
using assembly creates a tar ball that contains several jars. specifying those jars in the classpath is a little bit of hassle. using the shade plugin make it consistent with how we create the parquet pig bundle