Write/delete ALL records

New feature added: extract or delete "ALL" records in the database.

MEDLINE 2015: truncated

Updates for 2015 DTD changes.
New feature: remove "(ABSTRACT TRUCNATED AT xyz WORDS)" from abstracts (moved to new flag truncated)
MEDLINE output now default and written as single stream to STDOUT

SQLite fixes

Fixed issue with SQLite queries for more than 999 records.

first citable release (DOI)

this release provides a DOI for medic

DB Schema improvements

A better relational schema for the abstracts and citations.