ghostscript: modernize
ghostscript: add test

Closes #35302.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
requirement: add cask and download attributes.

Print out the message pointing to the Cask and/or download location too.a
unsigned_kext_req: use new cask/download DSL.
Set cask and download DSL values on requirements.

Closes #35257.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
boost: add test

Closes #35303.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
boost: update 1.57.0 bottle.