cartopy v0.18.0

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[conda-forge-linter]

Hi! This is the friendly automated conda-forge-linting service.

I just wanted to let you know that I linted all conda-recipes in your PR (recipe) and found it was in an excellent condition.

I do have some suggestions for making it better though...

For recipe:

• License is not an SPDX identifier (or a custom LicenseRef) nor an SPDX license expression.

[xylar]

@conda-forge-admin, please rerender

[xylar]

@conda-forge-admin, please rerender

[xylar]

@conda-forge/cartopy, anyone have time to review this before I merge? I'd like to merge early this week if possible.

[xylar]

@conda-forge-admin, please rerender

[ocefpaf]

@conda-forge/cartopy, anyone have time to review this before I merge? I'd like to merge early this week if possible.

Sorry, I stole your merge ;-p

[xylar]

Sorry, I stole your merge ;-p

No worries. I't a big enough update and I had to make enough changes that I thought it was worth having another pair of eyes on it.