Allow LD_LIBRARY_PATH read from config

[am11]

Currently we support reading LD_LIBRARY_PATH from host and from ELF section. This PR adds third option to read from config to improve the command-line experience.

# before
$ LD_LIBRARY_PATH=/tmp/linux/lib:/tmp/linux/usr/lib:/tmp/linux/lib/x86_64-linux-gnu:/tmp/linux/usr/lib/x86_64-linux-gnu \
    ops run -c config.json publish/myApp

# after: config.json has the Env section:
#    "Env": {
#      "LD_LIBRARY_PATH": "/tmp/linux/lib:/tmp/linux/usr/lib:/tmp/linux/lib/x86_64-linux-gnu:/tmp/linux/usr/lib/x86_64-linux-gnu"
#    }

$ ops run -c config.json publish/myApp

[am11]

@eyberg, would it be possible we get a new release at this point?

[eyberg]

yeh it's been a while - went ahead and cut a new version