add branch policy to readme
remove errhandler_index from protected call handling, and fix call sites in Duktape internals
fix protected/safe call sites in api test cases to omit errhandler_index
fix runtests to omit errhandler_index
fix protected/safe call sites in code examples to omit errhandler_index
release note update
fix some api testcases to use TEST_SAFE_CALL to reduce duplication
fix some api testcases to use TEST_SAFE_CALL to reduce duplication