Starting Julia on Windows fails if JULIA_HOME is set

[veita]

OS: Windows 7
Install Julia 0.3.11. Set JULIA_HOME=C:\devel\julia-0.3.11 as system environment variable.
Try to start Julia with the desktop link created by the setup.

-> Julia does not start.

The error message was System image file "C:\devel\julia-0.3.11\../lib/julia/sys.ji" not found.

[tkelman]

That variable is significant. If you're going to set it, it needs to be set to the location of the julia.exe executable, or things are going to break. That's also true on other platforms.

[tkelman]

We could still maybe use some docs on this and other significant environment variables.

[veita]

OK, this seems to be quite uncommon. Normally the home variables reference the installation directory, and the executables reside in a bin directory below (see e.g. JAVA_HOME, GROOVY_HOME, SCALA_HOME, ERLANG_HOME, or R_HOME).

[tkelman]

ref #9981