Some app descriptions + imager is a required pkg

[lindsayplatt]

1. Add imager as a required package to viz.yaml. Actually, it should be installed when you install vizlab.
2. All app descriptions for add in short description of each application at the top of the page.  #107.

[eread-usgs]

@lindsaycarr I'd prefer to review this text on test- easier on the eyes. I'm good w merging it after walker gives it a review.

Also, @wdwatkins I just noticed that there's a timezone indicated here in the metadata- is that from GA or manually added? Either way, if it is reliable indication of timezone set by the admin and is consistently known for each app, would you please add that to the time of day plots for each figure?

[eread-usgs]

@wdwatkins and @lindsaycarr I just looked and saw that most apps do have timezones, some don't. Since most of the apps do have timezone, and I believe @wdwatkins said there's not an automated way to bring this in, can one of you please add, manually, the time zones set by the GA administrator to each app that does not have that info? @wdwatkins has access to all of the accounts, so it's probably easiest for him to take on. Please work on this in the next week or so- let me know if you don't have availability for that. related to #102 #102

[wdwatkins]

You can get the timezone for the particular account from google, it's just not a part of the normal fetch workflow. I can add them to any that are missing.