Fix napa console when using IRB.
Fix napa console when using IRB.

IRB was taking extra arguments, "console" and optionally the environment, when running `napa console <environment>`. IRB then interprets this as a script name, and errors out. These arguments are now removed from ARGV before starting the interpreter.

ywong19/napa,EmilioCristalli/napa,rgaidot/napa,darbyfrey/napa,bellycard/napa,babyvote/napa,ashtonthomas/napa,shaqq/napa