JS: add a splitting function to get a list of sub arguments
JS: add a splitting function to get a list of sub arguments

Based on InputAgent.splitStringVectorByBraces which essentially splits keyword
input into subargument ranges for individual parsing.

Signed-off-by: Harvey Harrison <eadbd6b462bf3c97df0300a934c12bc2e5d1fe51@ausenco.com>

jaamsim/jaamsim,jaamsim/jaamsim,jaamsim/jaamsim,jaamsim/jaamsim