Merge pull request #73 from brainstorm/master

Extend simNGS test to generate 100 simulated reads from each organism and spike an ecoli read on each of them
Added fastq_screen_db parameter to the config loader
Merge branch 'master' of https://github.com/guillermo-carrasco/facs
Use FACS_DB parameter from the config file instead of the old DB [ci skip]
Merge branch 'master' of https://github.com/guillermo-carrasco/facs
Modify fastq_screen test to test single_threaded, single databases
Accomodate for @guillermo-carrasco multi-db logging