Forkproperties regression with Jetty

[mecseid]

With commit 79ac348, Jetty cannot start, because the split makes empty sytem properties.
I get a startup failure with stactrace about empty key.

Based on the mentioned commit, a simple example:

jshell> "-Dsome.property=value".split("-D")
$1 ==> String[2] { "", "some.property=value" }