Improve parquet-schema and parquet-read CLI tools

[sadikovi]

This is a follow-up of #156.

CLI tools parquet-schema and parquet-read could be improved with a better help message and parameter support, since the current version of both tools has a basic functionality, which is enough for now, but it is not very extensible and lacking support of complex argument parsing.

For example, it would be good to display data as a table or support printing in JSON or CSV. For schema, it would be good to print just schema, or list all row groups/column chunks, or display the extended version that includes dictionary/index page offsets and statistics.