Readme should be clearer about Quick Sync mode

[robspearman]

It took me a while to realize that specifying a target and initiator causes osync to completely ignore the config file you pass it.

Suggest making this explicit in the Readme.

Also would seem useful to warn with a message when using or not using a config file user has specified on the command line.

[deajan]

Good idea. Will add to doc ;)