Description of the issue

There are a few GMT modules that have a mode for extracting data (statistics or otherwise) via the inquire (I) flag in addition to plotting:

• rose - Wrap rose #794
• solar - Wrap solar #804, also has an -M mode where no plotting occurs
• histogram - Wrap histogram #563

How do we want to handle these cases? It seems weird to use fig.histogram(..., inquire=...) if no figure/plot is actually returned. One suggestion made at #794 (review) was:

Ideally, what we might have to do is make two user-facing rose functions:

1. A plotting-only `fig.rose`

2. A non-plotting `pygmt.rose` which will solely use the inquire (I) flag.

Both of these could share a core def _rose() function and live within pygmt/src/rose.py. This is just an idea though, and probably quite hard to implement in one Pull Request. For now, we could implement just the plotting side (1) and raise a NotImplementedError for inquire (I), and perhaps wrap pygmt.rose (2) in a future PR? Or maybe there's a smarter alternative way.

Open to suggestions on how we want the API for this look like.

Are you willing to help implement and maintain this feature? Discuss first