Ryan Davis is tipping his beer to a world in moral and constitutional decline. Ruminating shortcomings, both inward and out, that seem to have settled into the standard, the Louisville-based journeyman defiantly declares he and his crew “the new vigilantes of the two-drink minimum” on “Free from the Guillotine,” the dryly pugnacious opener to Ryan Davis & the Roadhouse Band’s Dancing on the Edge, the latest and perhaps greatest notch in the storied songwriter’s belt.