Tease apart models_filegroup vs install_data

[jwnimmer-tri]

Delete unused PendulumWithFriction.urdf.

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I've tested locally and the list of installed files is the same between this PR and the master branch.

Closes #11010.

Towards #15774.

FYI https://drake.mit.edu/stable.html#model-files

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This change is 

[jwnimmer-tri]

+@EricCousineau-TRI I think you get right of first refusal for this review. If you're busy, we can push it to @sammy-tri instead.

[jwnimmer-tri]

Reviewed 34 of 34 files at r1, 12 of 12 files at r2, all commit messages.
Reviewable status: LGTM missing from assignee EricCousineau-TRI(platform) (waiting on @EricCousineau-TRI)

[EricCousineau-TRI]

, beautimous! Small nit on globbing, though maybe it's pre-existing.

Reviewed 23 of 34 files at r1, 12 of 12 files at r2, all commit messages.
Reviewable status: 1 unresolved discussion (waiting on @jwnimmer-tri)

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tools/skylark/drake_data.bzl line 36 at r2 (raw file):

    ]
    exclude = glob_exclude + [
        "**/test/*",

nit (pre-existing) It's not clear to me how intuitive this exclude pattern will be for testonly = True.

Possible options:

• TODO
• glob_exclude gains these defaults only when testonly = False
• The default values are these, explicitly, perhaps via global constant DEFAULT_GLOB_EXCLUDE, but users can override them. Docstring says they should?

[jwnimmer-tri]

Reviewable status: 1 unresolved discussion (waiting on @EricCousineau-TRI)

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tools/skylark/drake_data.bzl line 36 at r2 (raw file):

Previously, EricCousineau-TRI (Eric Cousineau) wrote…

nit (pre-existing) It's not clear to me how intuitive this exclude pattern will be for testonly = True.

Possible options:

• TODO
• glob_exclude gains these defaults only when testonly = False
• The default values are these, explicitly, perhaps via global constant DEFAULT_GLOB_EXCLUDE, but users can override them. Docstring says they should?

Aha! Thanks, I'd meant to circle back here and totally forgot.

There are no tests that use this. I've update the docs.

PTAL.

[EricCousineau-TRI]

Reviewed 1 of 1 files at r3, all commit messages.
Reviewable status: complete! all discussions resolved, LGTM from assignee EricCousineau-TRI(platform) (waiting on @jwnimmer-tri)

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tools/skylark/drake_data.bzl line 36 at r2 (raw file):

Previously, jwnimmer-tri (Jeremy Nimmer) wrote…

Aha! Thanks, I'd meant to circle back here and totally forgot.

There are no tests that use this. I've update the docs.

PTAL.

OK Sweet ,thanks!