Addition of filtered biomarker blast report

This release includes a fix to #150 where uninitialized databases to mob_typer would result in confusing error messages. Additionally, this release includes the addition of a new biomarkers blast report file which will be automatically generated by mob_recon and optionally by mob_typer if the --biomarker_report_file parameter is included. This file contains the filtered biomarker blast results for oriT, replicon, relaxase, and mate-pair-formation as a single tab-delimited file of blast results with an included column labelling which biomarker type the sequence belongs to.