Implement a custom HystrixPropertiesStrategy plugin

Add a custom HystrixPropertiesStrategy implementation where getCommandPropertiesCacheKey is overridden
to return null so that HystrixPropertiesFactory will always generate a new HystrixCommandProperties for
each new HystrixCommand instantiation.
Change CachelessHystrixPropertiesStrategy to a normal class

Apparently you can only register a strategy once inside a single Java process and
subsequent attempts will cause exceptions to be thrown.

Instead of registering in Global, which, depending on libs/other singletons/w/e,
may already be too late, use the hystrix.plugin.HystrixPropertiesStrategy.implementation
system property and name our class.
Check and try to set Properties Strategy in Global

Might be a good idea to try to make sure CachelessHystrixPropertiesStrategy is used in Global
during onStart if the system property is not set
Switch to KeyAndBuilderValuesHystrixPropertiesStrategy
Make the mapper ignore null values
Be less controlling about HystrixPropertiesStrategy
Merge pull request #36 from lloydmeta/feature/cacheless-hystrix-properties-strategy

Implement a custom HystrixPropertiesStrategy plugin
Merge branch 'develop' into feature/optional-part-description