[flow] vm: Fixes NNOT result type

Change-Id: I7dc903f3c665161551476298d47a1b60cb100cec
[flow] parser: fixes repeative not operator parsing

Change-Id: Ib745d65c4762560035fab07063230230a0ac8ecb
updates

Change-Id: Iddd841d2b9ecc6148e93eec462fe48134a8c0677
[flow] implements unary minus and fixes logical OR expression evaluation.
cleanup