D-Net

#1498 introducing major citations related refactoring including new generic direct citation matching moved to processing phase, introduced position field in all citations schemas and updated collapser taking position into account when merging citations details coming from 3 variuos sources: fuzzy citationmatching, direct citationmatching, references metadata

#1257 dropping schema generation related hacks in all PIG modules, switching to literal schema parameters

#1257 renaming 'eu.dnetlib.iis.avro.map.output.value.class' property (which become obsolete) required by CollapserReducer to 'collapser.reducer.schema.class'.

#1257 dropping schema generation related hacks in all map-reduce modules, switching to literal schema parameters

#1176 updating description

#1176 introducing side products removal in multiple_input_collapser by maintaining sideproducts_removal flag

#1133 dropping useless workfing_dir creation for pig nodes

#1022 introducing PMC extracted document metadata collapser removing duplicates before sending output to PMC citation ingestion module

#577 renaming origins to matched and ingested

#577 fixing PMC citations collapser by executing toString() on text when retrieving map value