Pheweb

- Fixes `pheweb cluster`.

- Fixes uppercase `field_aliases` in `config.py`. Column names are case-insensitive now.

- Speeds up autocomplete

- Adds beta/sebeta columns to the tables on /pheno/ and /variant/
- Shows AF range or MAF range better on /variant/
- Shows pvalue=0 as p<1e-320 in most places.
- Improves error-handling on /pheno-filter/
- Upgrades to LocusZoom.js 0.13, including new PNG downloads
- Fixes bugs in OAuth and WSGI
- Uses relative redirects, so that http vs https and hostname don't matter, except in OAuth code.

- Improves hovering on the filtered manhattan plots
- Includes code for annotating with VEP
- Shows category on /top_hits

**Changes needed to data:**

- Run `rm generated-by-pheweb/top_hits.json; pheweb top-hits`

- Uses gencode v37 (released 2021-Feb)
- Shows GClambda and num_samples/num_cases/num_controls and num_loci<5e8 on /phenotypes
- Supports custom_templates/ again

**Changes needed to data:**

- Run `rm generated-by-pheweb/sites/sites.tsv && pheweb process` (because gene names must agree beween autocompletion and the pre-processed data)