partial fix for issue 71 - leading negative numbers in expressions no longer confuse option parser
partial fix for issue 71 - leading negative numbers in expressions no longer confuse option parser

mcenirm/csvfix,mcenirm/csvfix,ausonweng/csvfix,jheusser/csvfix,ausonweng/csvfix,jheusser/csvfix,mcenirm/csvfix,mattgascoigne/csvfix,ausonweng/csvfix,mattgascoigne/csvfix,jheusser/csvfix,mattgascoigne/csvfix