Add ability to pass in wemo address as msg.ipaddr.

[kerber]

Inspired by http request I've modified the Wemo out node to handle passing in a device address as msg.ipaddr.

[coveralls]

Coverage remained the same at 86.8% when pulling e96c65c on kerber:patch-1 into 36ac381 on node-red:master.

[kerber]

I apologize for the pull request without CLA. I hadn't read the contributing guide. I'm happy keeping my own branch.

[dceejay]

Hi @kerber,
would you like to complete the CLA to get this PR in ? Or shall we close ?
If the former - then would it make sense to update the html file to add the option to the help/info panel ?

[kerber]

Hey @dceejay,
I'm just going to close this pull request. I ended up not using the modified code and I'm a bit swamped with other projects at the moment. Sorry for leaving it open for so long!