* k8s: add tolerations for 'nodeType=crawling:NoSchedule' to allow scheduling crawling on designated nodes for crawler and profiles jobs and statefulsets
* add affinity for 'nodeType=crawling' on crawling and profile browser statefulsets
* refactor crawljob: combine crawl_updater logic into base crawl_job
* increment new 'crawlAttemptCount' counter crawlconfig when crawl is started, not necessarily finished, to avoid deleting configs that had attempted but not finished crawls.
* better external mongodb support: use MONGO_DB_URL to set custom url directly, otherwise build from username, password and mongo host
- use statefulsets instead of deployments for mongo, redis, signer
- use k8s job + statefulset for running crawls
- use separate statefulset for crawl (scaled) and single-replica redis stateful set
- move crawl job update login to crawl_updater
- remove shared redis chart
package refactor:
- move to shared code to 'btrixcloud'
- move k8s to 'btrixcloud.k8s'
- move docker to 'btrixcloud.docker'
