jsk_pr2_startup: specify prefix for laser_filters plugins

[furushchev]

According to PR2/pr2_navigation#27

[k-okada]

So, we did not use shadow filters until now?

[k-okada]

does this mean , if we PR2/pr2_navigation#27, we have to update our file?
or both PR2/pr2_navigation#27 and jsk_robot has wrong settings for laser filter and they are not working correctly right now. ?

[furushchev]

@k-okada We have now a pipeline as followings:

Since the actual change before/after the pull request is only angular_bounds according to the discussion at PR2/pr2_navigation#27 , /tilt_scan_shadow_filtered and /tilt_scan_filtered topics should be affected.

So, we did not use shadow filters until now?

I think we usually use /tilt_scan raw topic in most cases. That's why we did not notice the problem here.

both PR2/pr2_navigation#27 and jsk_robot has wrong settings for laser filter and they are not working correctly right now?

Both settings now occur wrong behaviors. So I think it is ok to merge both upstream PR and this.
I checked it fixes the problem after patching this PR.

BEFORE

AFTER