Adjust development branches libraries warning to specify the branch (#1979)

[daveoconnor]

Adds master and develop to the version warning notification.

[rbbeeston]

I'm not sure if that's the best wording. Seems like it's telling you to go somewhere else, instead of where you currently are.

Perhaps "This version of Boost is under active development. You are currently in the Develop (or Master) Branch, The current version..."

[karimarie67]

I have a question @rbbeeston. Are we ever in "active development" in master? I'm confused on this messaging. You are in master (when boost.org) unless you, as the user, changes it to develop. Maybe I'm misunderstanding this 🙂

To clarify, I meant from the list page and physically changing to develop!

[rbbeeston]

@karimarie67 Theoretically, master should be the same as the current version, but because it could be updated, like during beta, we would want to point users to the current version as a rule, as master could potentially be different near releases.

[daveoconnor]

Copy updated.

[sdarwin]

Boost releases occur every 3-4 months.
Almost all the time, both master and develop represent "forward development". Neither would be the same as the current version, 1.89.0. Except for a very brief time when a release is published.

[karimarie67]

Thank you all - I was thinking more narrow, more toward website-v2 workflows which is completely different. I appreciate the help!