inputParser.m: Re-architect internal data structures for 60% speed improvement. Key idea is to replace Parameter and Switch structs with name field containing a nested struct (def, val fields) with a struct array that has fields "name", "def", and "val". This makes it possible to eliminate for loops. * NEWS.9.md: Announce performance improvement. * inputParser.m: Declare "Parameter" and "Switch" properties as struct arrays. Add new private property "last_idx" which caches the last Parameter or Switch lookup. * inputParser.m (addRequired): Adjust input validation to use numel() now rather than numfields(). * inputParser.m (addOptional): Adjust input validation to use numel() now rather than numfields(). * inputParser.m (addParameter): Change code to add new Parameter to a struct array. * inputParser.m (addSwitch): Change code to add new Switch to a struct array. * inputParser.m (parse): Adjust initialization of internal variables ParameterNames and SwitchNames to match new data structure. Use last_idx to simplify call to validate_arg() for Parameters. * inputParser.m (validate_arg): Move creation of error message to code path when error has been found---No need to do it for every function call. Don't capture "exception" variable in try/catch as it is no longer used. * inputParser.m (is_argname): Cache "last_idx" if match was found. * inputParser.m (add_missing): Replace call to setdiff() with in-place code which can take advantage of implicit knowledge to eliminate calls to unique and input validation. Replace for loop with cell2struct/struct2cell combination.