Solves message on instanceof and "==="

I got messages on code like:
```
if ($a instanceof \MyClass === false && $b = true)
```
Saying "Implicit true comparisons prohibited; use === TRUE instead"

(I wanted to report a but through PEAR, but gave me headaches)

Applying this patch will allow 
```
if ($a instanceof \MyClass === false && $b = true)

if ($a instanceof \MyClass === true && $b = true)
and
if ($a instanceof \MyClass && $b = true)
```