remove unused variable.
move functions for data stream chopping into child classes, clean
up the data stream chopping process a bit.
Convenience: print file name again.
Add CMSPixelStreamDecoderRAL inheriting from CMSPixelFileDecoderRAL
but accepting std::vector<uint32_t> instead of a file pointer as
input data source.
Add implementation of Constructor and chop_datastream for CMSPixelStreamDecoderRAL
Move check for data stream outside get_event to be compatible with streamdecoder,
which now overwrites the check.