make barrier=kerb subtler

[mkoniecz]

What steps will reproduce the problem?

1. create barrier=kerb way
2. create barrier=cliff way

What is the expected result?

These ways are easy to distinguish

What happens instead?

kerb is stronger than cliff. Maybe make tooths smaller/smooth?

Please provide any additional information below. Attach a screenshot if possible.

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2017-10-30 23:58:23 +0100 (Mon, 30 Oct 2017)
Build-Date:2017-10-31 02:33:18
Revision:13064
Relative:URL: ^/trunk

Identification: JOSM/1.5 (13064 en) Linux Ubuntu 16.04.3 LTS
Memory Usage: 959 MB / 959 MB (192 MB allocated, but free)
Java version: 1.8.0_151-b12, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Screen: :0.0 1920x1080
Maximum Screen Size: 1920x1080
Dataset consistency test: No problems found

Plugins:
+ OpeningHoursEditor (33185)
+ buildings_tools (33735)
+ lakewalker (33712)
+ reverter (33572)
+ undelete (33480)

Map paint styles:
- https://josm.openstreetmap.de/josmfile?page=Styles/AdvertisingStyle&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/MaxspeedIcons&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/LessObtrusiveNodes&zip=1
- ${HOME}/Documents/install_moje/josm_style_sidewalks/Styles_Sidewalks-style.mapcss
- https://josm.openstreetmap.de/josmfile?page=Styles/NumberedWalkingNodeNetworks&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/HU-HighlightHikingTrailSigns&zip=1
- https://josm.openstreetmap.de/josmfile?page=Styles/Fixme&zip=1

Validator rules:
+ ${HOME}/Documents/install_moje/josm_validator/josm.validator.mapcss

Last errors/warnings:
- W: java.net.SocketException: Socket closed
- E: java.net.SocketException: Socket closed
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out
- W: java.net.SocketTimeoutException: Read timed out