osslsigncode: add libgsf optional dependency.

Closes #26009.
Closes #26026.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
bottle: use new quoting style.
CONTRIBUTING: shorten troubleshooting wording.
README: remove `brew server`.
README: add troubleshooting.
Add Formula directory README.
primesieve 5.0

Closes #26025.