Add LCParquetBase for making custom output processors.

The LCParquetBase class is a processor that does the following common actions required for writing Parquet files. It is now also used by the already existing LCParquet processor.

Properties

Defines the OutputDir parameter that dictates where the output file is stored.

Initialization stages

Calls printParameters to be nice.

Initializes a protected _fs member variable of type std::shared_ptr<arrow::fs::FileSystem>. Child classes should use this to create all necessary files.

Use In Other Packages

All includes now start with LCParquet/ (ie: LCParquet/EventFile.hxx).

Move helper functions like getCollection and addIndexToCollection into a public LCPQHelpers.hxx header to allow reuse by other packages