10, etc: Consider repositioning Waku "resource-restricted" to "efficient" to be more positive

[jimstir]

Reference issue: vacp2p/rfc#467
Author: oskarth

Problem

There have been cases where people, including protocol devs, take "resource restricted devices/environments" to mean that Waku only focuses on this. And that, therefore, there's a need for some other protocol that doesn't have this restriction.

This presents a false picture. One idea to focus it to be more positive, such as being efficient, running everywhere, and being modular. We are doing this to some extent in https://rfc.vac.dev/spec/10/ but could probably do it better.

Also Nimbus seems to have encountered a similar problem, cc @arnetheduck

Acceptance criteria

• Consensus on, if, and how to re-phrase it
• Updated main specs