Review request to remove the launcher workaround for tools multiple entry points

[Mandy Chung]

We implemented a temporary workaround for the tools module to contain
the multiple entry points [1].  Now with module views support [2],
we can remove that workaround:

    http://cr.openjdk.java.net/~mchung/jigsaw/webrevs/tools-launcher-fix/

This also includes a fix in the launcher that ignores CLASSPATH
environment variable if set but -m is specified (launching a modular
application).

Thanks
Mandy
[1] http://hg.openjdk.java.net/jigsaw/jigsaw/jdk/rev/2661318d6cfe
[2] http://hg.openjdk.java.net/jigsaw/jigsaw/jdk/rev/01d6b2c9d36d