Allow Custom Attachments

[NNovoa-CDWR]

Add field to the Web UI notifications page that allows used to select additional files to attach to the Facilities e-mail alert.

[dslosky-usgs]

@NNovoa-CDWR what kinds of files are you trying to attach? Additional shakemap products? Or files you're generating outside of shakecast? I think there's a use case for both, I'm just curious

[NNovoa-CDWR]

I am trying to attach a pdf file generated outside ShakeCast. We are using ShakeCast to alert our personnel that inspections needs to be performed and would like to attach the inspection forms they need to fill out.