run_installer as an alias to run_always

[MicaelJarniac]

How would this feature be useful?

run_always has a misleading name.

Flag	run	run_always
No flag	✅	✅
-R	✅	❌
--install-only	❌	✅

It doesn't "always run", as the name implies.

Describe the solution you'd like

Add an alias to session.run_always, like session.run_installer, that makes it clear that it's meant to be used to run commands to install things. This would make sense with its current behavior of not running with -R.

This could then become the recommended method, and run_always could be kept for backward compatibility.

Describe alternatives you've considered

No response

Anything else?

No response

[cjolowicz]

Fixed in #770