MB-30041: Migrate ValuesShouldFail to nlohmann::json
MB-30041: Migrate ValuesShouldFail to nlohmann::json

Migrate settings.cc to nlohmann::json by migrating individual
handlers, which requires interim parsing of cJSON objects
to nlohmann::json objects.

Migrate non<Type>ValuesShouldFail in config_parse_test to
nlohmann::json.

Change-Id: Idbd0769c68e8fdfbfe742c9b99db2425da8a0e3b
Reviewed-on: http://review.couchbase.org/100234
Tested-by: Build Bot <80754af91bfb6d1073585b046fe0a474ce868509@couchbase.com>
Reviewed-by: Trond Norbye <60edd2ef23891a753f231b0c6f161dc634079a93@gmail.com>

daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine,daverigby/kv_engine