Programmatically return job results

This pull request removes the hard coded links to job results in the analysis results page and instead makes the job object return actual filepaths to html files or result files. It uses glob to search through directories for html pages or, if a single file result, adds that file as a job result.
I see that we cannot use ```qiita_db.util.convert_to_id``` here because the field is called 'status' in that table (rather than 'job_status').  Should we consider updating these types of lookup tables to use the convention expected by convert_to/from_id?