Bug Fixes for Commands

• The touschek_scatter command was using the minimum of the absolute values of the positive and negative momentum aperture, rather than using both the positive and negative values. This resulted in pessimistic calculations of the Touschek lifetime.
• The chromaticity command chrom now performs a minimum of one correction step to ensure tht values are stored in variables used by optimize command.
• There was a bug in the ramp_elements and modulate_elements commands that resulted in problems handling multiple elements with the same name. This was fixed.
• Closed orbit correction was not respecting the closed orbit iteration parameters when computing the response matrix from closed orbits. This bug was pointed out by V. Sajaev (ANL).