optString fix from upstream JSON-java commit 6394d92279023dbfbd910ef9ee8895b1899860d5
optString fix from upstream JSON-java commit 6394d92279023dbfbd910ef9ee8895b1899860d5

d10xa/groovy-wslite,glaforge/groovy-wslite,jbellassai/groovy-wslite,jwagenleitner/groovy-wslite