refactor language from standards to guidelines

[chrstngyn]

@rkoskela - Avoid using Standards as a term if you're not a standards body. Perhaps we can refactor standards to guideilnes. Best practices may be better? Standardized? Can raise red flags in some communities

We want to make our intention clear that we want to establish a practice that should be adopted broadly across multiple communities

[chrstngyn]

Related discussion: #307

[cmbarton]

More detail in #314 Probably should merge