Add TeV catalog to gamma-sky.net

[vorugantia]

In this PR, I've mainly been working to add our new TeV catalog (from gamma-cat) to the website. This is what I've done:

• Load new TeV catalog in catalogs.py
• Show TeV catalog in MapViewComponent
• Show new data in the detailed view in CatViewComponent

The app is running perfectly. However, I ran into some problems along the way that I need to fix later (either in this PR or another one):

• Right now, in catalogs.py, I cannot dump data from all columns of the TeV catalog and convert it to JSON with pandas. Here is the error message I get:

ValueError: Cannot convert a table with multi-dimensional columns to a pandas DataFrame.

Because of this, I haven't added distance and spectral info to the detailed view in CatViewComponent. Right now it just displays the names and positions of each source. I'm not sure how to work around the error. Maybe I should just ignore all multi-dimensional columns for now?

• I've started to split up the one popup component into four separate components, each one containing a unique HTML template for their respective catalog. Although I'm halfway there, and the code works as-is, configuring the popup in MapComponent still looks very messy and should be fixed.

@cdeil - Can you take a look at the code when you're free to see if I'm headed in the right direction? Also, do you have a solution for the Python error I mentioned above? After this PR is closed we should be ready to publish the new website.

[cdeil]

@vorugantia - This sounds great!

And yes, we should deploy a new version of the website once gamma-cat is added. I don't know if it's a good idea to post to ArXiv during the holidays, it might get lost in people's inboxes, and posting in January is smarter.

Unfortunately I don't have time for code review before the holidays. (HESS survey paper goes to collaboration circulation tomorrow.)

So my suggestion would be that if you have something working, merge it. And if you have specific other questions or things I should look at, ping me again.

[vorugantia]

• I'm now dumping all of the fits file except for SED (multidimensional) data into the pandas dataframe.

• Popups fully reconfigured - code is much cleaner now.

Merging this PR...

[cdeil]

Thanks!

I tried this locally just now and it works for me.