Update golang.org/x/net commit hash to e18ecbb

See merge request ai3/accountserver!26

Disk usage

See merge request ai3/accountserver!27

We're now making all the asynchronous requests to aux-db from a single
backend wrapper (hence the rename as it's no longer just webapp data),
with a more generalized structure for resource-based lookups.

Use aux-db to retrieve cms_info data

See merge request ai3/accountserver!20

Internalize the webappdb.App type (part of CMSInfo).

Replace the dedicated 'webappdb' service with generic aux-db
lookups.

Update golang.org/x/net commit hash to 9060382

See merge request ai3/accountserver!25

Update golang.org/x/net commit hash to 5f55cee

See merge request ai3/accountserver!23

Update golang.org/x/sync commit hash to 036812b

See merge request ai3/accountserver!24

Update golang.org/x/crypto commit hash to 5ea612d

See merge request ai3/accountserver!22

Update golang.org/x/crypto commit hash to b8e89b7

See merge request ai3/accountserver!21

Refactor the errors to be compatible with Go > 1.13 error wrapping
idiom.

Update golang.org/x/net commit hash to 5f4716e

See merge request ai3/accountserver!19

This will make it easier in the future to replace the implementation
with one that is resource-aware (as input to lookup() is no longer
just a list of 'sites').

Publish per-op counters for all backends (ldap, cache).

Update module go-test/deep to v1

See merge request ai3/accountserver!17

Update module yaml to v2.4.0

See merge request ai3/accountserver!16

Update module sethvargo/go-password to v0.2.0

See merge request ai3/accountserver!15