Stake Mining Settings Optimised

- stake split threshold introduced;
- small inputs combined and average inputs are never split;
- bug fix: combine threshold must be reached, not necessarily exceeded.

These optimisations also decrease average stake transaction size.
addnode and getaddednodeinfo RPC Commands Added
Byte Counters Added to getpeerinfo
Version and Checkpoints Updated
Version and Checkpoints Updated (cont'd)
Merge pull request #5 from ghostlander/master

Orbitcoin v1.4.2.1