"for each" fix, for modified prototypes

Fix "for..each" in case Array or Object prototypes are modified globally.
more improvement for changed Object.prototype

more improvement for globally changed Object.prototype.
real_opt is the real option in the tmp_arr object, otherwiese it could be globally set prototype property.
Merge pull request #161 from yadimon/patch-2

"for each" fix, for modified prototypes