node: ignore exit status when starting portmap

[iwd32900]

This fix continues the work of a23866d, which only hit one of two calls to portmap.

[cancan101]

This does not seem like a right solution to the problem.

[iwd32900]

It may not be an ideal solution, but it works, and it's the one that was previously implemented incompletely. Whatever solution is ultimately adopted, it should be applied in both places.

As noted in the older commit's message, the portmap calls are only needed for older versions of Ubuntu. Newer versions use rpcbind instead, and don't seem to need any call at all in this location.

However, the fact that StarCluster calls portmap and cares whether it succeeds is causing problems for everyone who wants to use StarCluster with Ubuntu 14.04 LTS. (Since 13.04 is now EOL, the only supported official AMI is 12.04 LTS.) Unfortunately there is not an official 14.04 AMI yet. But to make it work, people have to create a fake portmap that is basically /bin/true. If we ignore the return value, modern Ubuntu is one step closer to working out of the box, and these calls to portmap could eventually be retired.

[cancan101]

Why not check for the existence for rpcbind or portmap and just call the right one?

[cancan101]

Along the lines of #435

[iwd32900]

This request is redundant with #435, and it does have a nicer solution. If that one is going to be merged, then please disregard this one.