Let boolean operators (||, &&) evaluate to the value instead of the boolean equivalent

def a = 0
def b = null
def c = "a string"
def d = ""

def val = a || c // c gets evalutated, because the boolean equivalent of a (0) is false

assert a || b == null
assert c || d == "a string"
assert d || a == 0
assert a || "another string" == "a string"
assert d || "another string" == "another string"

def val = aMap?.aProperty?.aSubProperty || "a default Value"

myobject.aMethodThatReturnsNullWhenItFails() || myobject.anotherMethod() 
// myobject.anotherMethod gets only executed the result of the first call evalutes to false

if(a || b){...} // would still work

assert (0 || 15) instanceof Integer
assert !!(0 || 15) instanceof Boolean