Description of problem:
The calamari API allows creation of CRUSH nodes and CRUSH rules
but the validation of semantics are lacking.

for example you can
Make a new root node that contains all existing OSDs and the default crush rules will be very unhappy

rule replicated_ruleset {
        ruleset 0
        type replicated
        min_size 1
        max_size 10
        step take default
        step chooseleaf firstn 0 type host
        step emit
}

since we don't have hosts between the root node and the osd and the name of the root isn't called default this rule will not select any OSDs for pools using the replicated ruleset


Version-Release number of selected component (if applicable):


How reproducible:
100%

Steps to Reproduce:
1. POST {"bucket_type": "root", "name": "general", "items": [{"id": 0, "weight": 0.0, "pos": 0}]} to /api/v2/cluster/<FSID>/crush_node

2.
3.

Actual results:
HTTP 201

Expected results:
HTTP 4XX -- some validation error

Additional info: