Goldcoin Treasury Update (goldcoin#132)

* Bump MAX_MONEY for SB

Here we increase the MAX_MONEY constant to allow for the creation of the Treasury Superblock.

* Increase version number

Increase version release to 0.15.0.

* Define SB values

Define the address, amount, and height values for the Treasury Superblock.

* Add SB consensus rules

Add SB consensus rules and amount.h to includes.

* Update validation.cpp

Add treasury superblock logic to validation.cpp.

Remove stratum signaling

This patch fully restores the default mining configuration last seen in 0.14.8.

Merge pull request goldcoin#98 from microguy/goldcoin-master

Replace HMAC_SHA256 with new version

Update website

Update gitian build for focal

Update man pages

GLC -> GLC

Deactivate ACP with higher hashrates above a specific height