Improve CScriptNum() comment
Improve CScriptNum() comment

Edited-by: Pieter Wuille <c1fe694431f9243042d0eb4561d822ec1200493d@gmail.com>

domob1812/crowncoin,syscoin/syscoin,syscoin/syscoin,syscoin/syscoin,Crowndev/crowncoin,Crowndev/crowncoin,Infernoman/crowncoin,Infernoman/crowncoin,syscoin/syscoin,domob1812/crowncoin,Crowndev/crowncoin,syscoin/syscoin,Infernoman/crowncoin,domob1812/crowncoin,domob1812/crowncoin,syscoin/syscoin,Crowndev/crowncoin,Infernoman/crowncoin,domob1812/crowncoin,syscoin/syscoin,Crowndev/crowncoin,Infernoman/crowncoin,syscoin/syscoin,Infernoman/crowncoin,domob1812/crowncoin,Crowndev/crowncoin