v2.2.0.7

NET: Improve networking performance
NET: Remove support for old protocol versions that are no longer supported
RPC: Fix a crash in gettxoutsetinfo; Improve gettxoutsetinfo behaviour for new transaction output types
RPC: Fix GetNetworkHashPS calculation; It was incorrectly including witness 'work' in the mining calculation and returning an overly high number as a result
RPC: Introduce 'pow_time' and 'witness_time' fields to all block based RPC commands that include 'time' in the output; Change 'time' to display the most accurate time always (witness time if available, otherwise pow time)
MINING: Prevent mining of orphan blocks while wallet is still syncing on startup
UI: Fix a balance display issue some wallets were experiencing
CORE: Fix a rare crash that was being triggered in some nodes
CORE: Various performance improvements from removal of parts of the phase3 backwards support