add machine tag if statement

[aginika]

I added use_machine argument to change whether use machine tag or not.

[kohrt]

Hi,
is there a reason for having the machine tag to localhost optional?

[aginika]

When we include this file from other launch and we describe machine tag for localhost in other launch,
this will not be compatible with this machine tag.
Some people may want to disable this machine tag , so I made it optinal (But default is true).

[kohrt]

ok, that makes sense.