performance improvements: start-up time

[wardi]

CKAN version

master

Describe the bug

Slow start-up time for ckan affects the ckan cli, and is measured in seconds even with only a few plugins activated. This slows management tasks and local api usage with ckanapi.

Steps to reproduce

Run a cli command that should complete quickly with time, e.g. time ckan --help

Expected behavior

Quick completion, not

real	0m4.302s
user	0m3.884s
sys	0m0.284s

Additional details