Copy function mixes keys/values

[nkamapper]

This copy problem seems to occur when there is a space in one or more of the values.
But not always, so the order of the tags may perhaps matter.

What steps will reproduce the problem?

Copy the following tags from one object to another in JOSM, using either Edit->Copy Tags or the popup menu in the tag window:

boundary=national_park
name=Raet nasjonalpark
naturbase:iid=VV00003273
naturbase:verneform=NP
operator=Raet Nasjonalparkstyre
protect_class=2
related_law=https://lovdata.no/forskrift/2016-12-16-1632
short_name=Raet
start_date=2016-12-16
type=boundary
url=http://faktaark.naturbase.no/?id=VV00003273

What is the expected result?

The same tags.

What happens instead?

Note that several keys/values have been mixed:

Nasjonalparkstyre=protect_class=2
boundary=national_park
name=Raet
nasjonalpark=naturbase:iid=VV00003273
naturbase:verneform=NP
operator=Raet
related_law=https://lovdata.no/forskrift/2016-12-16-1632
short_name=Raet
start_date=2016-12-16
type=boundary
url=http://faktaark.naturbase.no/?id=VV00003273

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

URL:https://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2018-03-04 16:20:37 +0100 (Sun, 04 Mar 2018)
Build-Date:2018-03-04 15:24:13
Revision:13500
Redirecting:to URL 'https://josm.openstreetmap.de/svn/trunk':
Relative:URL: ^/trunk

Identification: JOSM/1.5 (13500 nb) Mac OS X 10.13.3
OS Build number: Mac OS X 10.13.3 (17D47)
Memory Usage: 1038 MB / 1820 MB (551 MB allocated, but free)
Java version: 1.8.0_161-b12, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Screen: Display 69732864 1440x900
Maximum Screen Size: 1440x900
VM arguments: [-Djava.security.policy=file:<java.home>/lib/security/javaws.policy, -DtrustProxy=true, -Djnlpx.home=<java.home>/bin, -Djava.security.manager, -Djnlpx.origFilenameArg=${HOME}/Library/Application Support/Oracle/Java/Deployment/cache/6.0/56/1ee8cfb8-40e36ffa, -Djnlpx.remove=false, -Dsun.awt.warmup=true, -Djava.util.Arrays.useLegacyMergeSort=true, -Dmacosx.jnlpx.dock.name=JOSM, -Dmacosx.jnlpx.dock.icon=${HOME}/Library/Application Support/Oracle/Java/Deployment/cache/6.0/16/47ee53d0-3ef1ec79.icns, -Djnlp.application.href=https://josm.openstreetmap.de/download/josm.jnlp , -Djnlpx.jvm="<java.home>/bin/java"]
Dataset consistency test: No problems found

Plugins:
+ PicLayer (34021)
+ SeaChart (33995)
+ apache-commons (33668)
+ conflation (0.5.6)
+ ejml (32680)
+ geotools (33958)
+ imagery-xml-bounds (34077)
+ jts (32699)
+ opendata (34072)
+ reverter (34036)
+ todo (30303)
+ utilsplugin2 (33991)

Tagging presets:
+ https://josm.openstreetmap.de/josmfile?page=Presets/LaneAttributes&zip=1
+ https://raw.githubusercontent.com/OpenNauticalChart/josm/master/INT-1-preset.xml

Map paint styles:
+ https://josm.openstreetmap.de/josmfile?page=Styles/Lane_and_Road_Attributes&zip=1
- https://raw.githubusercontent.com/OpenSeaMap/josm/master/INT1_Seamark.mapcss
- http://osm.wzh.be/josm/entur_1.0.mapcss

Last errors/warnings:
- W: No configuration settings found.  Using hardcoded default values for all pools.
- W: Warning: Failed to scan file 'site-svn.openstreetmap.org-_applications_editors_josm_plugins_opendata_modules.txt' for module information. Skipping.

[Don-vip]

The code does not like space characters in values and expects them to be quoted, as follows:

name="Raet nasjonalpark"
operator="Raet Nasjonalparkstyre"

[Don-vip]

In 13541/josm:

fix #16104 - better support of space characters in values for tags copy/paste