jaxws-maven-plugin doesn't make use of the maven toolchain

[andre-doherty]

hello,

The jaxws-maven-plugin is not making use of the maven toolchain configuration which leads to runtime issues when the generated bytecode / code is not matching the target jdk (eg using the wsgen goals).
As a matter of fact the old codehaus mojo had integrated the use the maven toolchain but this change was not reported in the sun plugin.
How to do this is described in the maven documentation :
https://cwiki.apache.org/confluence/display/MAVENOLD/Toolchains

I have implemented this in the following pull request :
#701

André