Stop listing network key in "Presets do not contain property value"

[mkoniecz]

it is a quick one-line fix, see r6369 (#9280) or r7225 (#10126)

alternative is maintaining absurdly long list of possible values (Starting from "BikeOne" and "PKP")

example: ​https://www.openstreetmap.org/node/1209860082 and ​https://api.openstreetmap.org/relation/176889

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2014-06-13 01:36:22
Last Changed Author: Don-vip
Revision: 7245
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2014-06-13 01:08:43 +0200 (Fri, 13 Jun 2014)
Last Changed Rev: 7245

Identification: JOSM/1.5 (7245 en) Windows 7 32-Bit
Memory Usage: 75 MB / 247 MB (15 MB allocated, but free)
Java version: 1.7.0_55, Oracle Corporation, Java HotSpot(TM) Client VM
Dataset consistency test: No problems found

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