Remove DRAKE_EXPORT from examples

[jwnimmer-tri]

Remove DRAKE_EXPORT from a examples. This is a portion of #3973.

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This change is

[jwnimmer-tri]

+@sammy-tri has accepted my invitation to review these. Thanks!

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Review status: 0 of 7 files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable

[sammy-tri]

Reviewed 6 of 7 files at r1.
Review status: 6 of 7 files reviewed at latest revision, 3 unresolved discussions.

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drake/examples/Atlas/atlasUtil.h, line 3 at r1 (raw file):

#pragma once

#include "drake/common/drake_export.h"

Remove this too?

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drake/examples/Pendulum/pendulum_swing_up.h, line 5 at r1 (raw file):

#include <memory>

#include "drake/common/drake_export.h"

Remove include as well?

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drake/examples/schunk_gripper/simulated_schunk_system.cc, line 3 at r1 (raw file):

#include "drake/examples/schunk_gripper/simulated_schunk_system.h"

#include "drake/common/drake_export.h"

Remove include also?

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Comments from Reviewable

[sammy-tri]

Reviewed 1 of 7 files at r1.
Review status: all files reviewed at latest revision, 3 unresolved discussions.

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Comments from Reviewable

[jwnimmer-tri]

Review status: 4 of 10 files reviewed at latest revision, 3 unresolved discussions.

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drake/examples/Atlas/atlasUtil.h, line 3 at r1 (raw file):

Previously, sammy-tri wrote…

Remove this too?

Done.

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drake/examples/Pendulum/pendulum_swing_up.h, line 5 at r1 (raw file):

Previously, sammy-tri wrote…

Remove include as well?

Done.

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drake/examples/schunk_gripper/simulated_schunk_system.cc, line 3 at r1 (raw file):

Previously, sammy-tri wrote…

Remove include also?

Done.

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Comments from Reviewable

[sammy-tri]

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Reviewed 6 of 6 files at r2.
Review status: all files reviewed at latest revision, all discussions resolved.

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Comments from Reviewable