Added morphline command to read from RCFile

This command parses an RCFile. RCFile can be read Row-wise or Column-wise.
 - Row-wise: One morphline record is emitted for each row in the RCFile. Each record will contain fields for all the columns configured in the columnMap
 - Column-wise: One morphline record is emitted for every row under columns defined in column map. A single column is read completely before moving to the next column. Order of columns is as defined in the columnMap.

The path of the RCFile is read from _attachment_name property in the input record.
For a RCFile with 5 rows and 5 columns. Row wise would emit 5 records and Column wise would emit 25 records.