[chuck-dev] allowing string references to be declared (PATCH)

Hi! This patch allows string references to be declared (should merge with v1.3.0.2 and SVN trunk). Seemingly works and allowed me to simplify some of my code involving static string members. Looking through chuck_scan.cpp, there are two more occasions where string references were disallowed but the checks have since been commented out. So I guess that this check has simply been overlooked. Best regards, Robin