Vectorize minMaxIdx functions

* Updated documentation and intrinsic tests for v_reduce

* Add other files back in from the forced push

* Prevent an constant overflow with v_reduce for int8 type

* Another alternative to fix constant overflow warning.

* Fix another compiler warning.

* Update comments and change comparison form to be consistent with other vectorized loops.

* Change return type of v_reduce_min & max for v_uint8 and v_uint16 to be same as lane type.

* Cast v_reduce functions to int to avoid overflow. Reduce number of parameters in MINMAXIDX_REDUCE macro.

* Restore cast type for v_reduce_min & max to LaneType