Small improvements: Alphabetic order for variables in model browser, module structure...

Small improvements: Alphabetic order for variables in model browser, module structure view displays where the selected variable is located in the module structure, game experiment progress displays the correct percentage when using output interval, withlookup expressions accept spreadsheet tables, modelicawriter uses model name instead of misguiding "Model_n", created a new "minmax" built-in function. (refs #3414)

git-svn-id: https://www.simantics.org/svn/simantics/sysdyn/trunk@25091 ac1ea38d-2e2b-0410-8846-a27921b304fc