Nornir-salt

BUG Fixes
- Improved ResultSerialiser function to detect failed tasks based on exception presence

BUG Fixes
- Fixed RetryRunner to properly detect tasks completion for all hosts
- Fixed RetryRunner to not timeout due to queue.get before all tasks completed

BUG Fixes
1. Fixed FFun has_filter breaking Nornir object initialization
2. Fixed RetryRunner to close connections before retrying them

FEATURES
1. Added tcp_ping task
2. RetryRunner - added reconnect_on_fail boolean parameter to reconnect to host on task failure
3. RetryRunner - added support for task_timeout timer to wait for task to complete for all hosts

CHANGES
1. RetryRunner - replaced LOCK acquire/release handling using with statement
2. Updated requirements to include Nornir, Netmiko, nornir_netmiko and nornir_napalm modules
3. Improved Task Failure detection logic for RetryRunner
4. Improoved RetryRunner reconnection logic and task completion detection

BUG Fixes
1. Fixed FFun has_filter breaking Nornir object initialization
2. Fixed RetryRunner to close connections before retrying them

Changelog
- Added FFun helper function
- Fixed RetryRunner issues with connecting via jumphost when host does not have extras defined
- Fixed RetryRunner connection retry logic for jumphosts