BibEdit: multiple improvements

• Integrate refextractor: use refextractor API to extract references from current record

• Multiple bugfixes and optimizations

• When field 999C5 is changed or inserted, add new subfield $$9 CURATOR to indicate that the field should not be automatically removed

• Add reference field template

• Remove lower capital indicator restriction (due to C indicator in references)

• When inserting a field in a given position, prefill field tag and indicators from the field above.

• If a cataloger edits a reference field, a subfield $$9 with value CURATOR is added automatically. If refextractor is run again, ensure that manually curated references do not get overwritten

• Perform an upload simulation of the marcxml to be submitted in order to detect possible errors (fixes #696)

• Shortcut fixes and selection mode available

• New button on top toolbar to allow the insertion of references to be analyzed by refextract, inside of a textarea