Merge 'dev' ~ v608 + fix errors/lints/warnings

less v643 (from http://www.greenwoodsoftware.com/less)

less v633 (from http://www.greenwoodsoftware.com/less)

Merge 'dev' ~ v590 + fix errors/lints + dev tooling fixes/improvements

less v608 (from http://www.greenwoodsoftware.com/less)

Merge 'dev' ~ v581.2 + fix errors/lints + dev tooling fixes/improvements

Merge 'dev' ~ 'v563' - buffer overflow fix + upgraded dev tooling

less v608-beta (from http://www.greenwoodsoftware.com/less)

less v603-beta (from http://www.greenwoodsoftware.com/less)

less v590 (from http://www.greenwoodsoftware.com/less)