Parameters: #225 - operator can enter fractions and signed numbers now
Parameters: localized numeric values, values rounded as per pattern (3 decimal places) on loss of focus
Parameters: validation of new values using metadata if available - GREEN=valid, RED=invalid, YELLOW=can't validate (metadata missing or broken)
Parameters: validation of known values (using metadata). Refactored 'range' & 'values' parsers into ParameterMetadata
Parameters: use bold typeface for changed values
Parameters: 'Edit' button on param info dialog -> list of valid values if provided by metadata for simplified editing
Parameters: cleanup
Merge pull request #352 from bob01/master_parameter_edit_validation

Parameters: fix #225, localization, validation and list selection of known values