Addition of HS60 ISO keyboard (#2972)

* Added Modular keyboards L,R and NUM

Created code modules for the 3 modules of the modular keyboard.
Original idea by MechboardsUK. Uses i2c implementation similar to lets
split

* Remove modular from master

This is to fix incorrect branching

* HS60 initial rgb port

porting HS60 to master rgb code

* HS60 fixes

* Hs60 rgb changes

* Cleanup for HS60 ISO

* More HS60 cleanup

* Update config.h

* More Cleanup for HS60

* HS60 modifications to work with configurator

* More HS60 cleanup

* Remove userspace layouts on HS60

* Update rules.mk

* HS60 bootloader change