Limiter handler: Added concurrentRequestsPercentage
Limiters: Added DEFAULT_NUMBER_OF_CONCURRENT_CONNECTIONS
LimiterHandler: Replacing decimal with float
Limiter Handler: Updating cache when add new limiter
Publishing message for new request
Fixing indentation
HeadingHierarchyFacter: Adding unit
Limiter model: Fixing add_or_update_limiter()
Fixing ApiServerTestCase