Metavar printing for options with action == 'callback'

[nh3]

Similar to #28, metavar are only printed for options with action == 'store'.

r-optparse/R/optparse.R

Lines 327 to 329 in 0ea3cca

	if( option@action == "store" ) {
	cat(" ", toupper(option@metavar), sep="")
	}

r-optparse/R/optparse.R

Lines 334 to 336 in 0ea3cca

	if( option@action == "store" ) {
	cat("=", toupper(option@metavar), sep="")
	}

[trevorld]

Thanks again for the bug report! Should be fixed now in the developmental version of optparse.