control-flow: IterationStatement body is not guraranteed to be executed
control-flow: IterationStatement body is not guraranteed to be executed

... unless it's a DoStatement or its condition is always true.
Fixes: #33

Also handle always false condition in ForStatement and WhileStatement.
And handle constant boolean condition in IfStatement.
Fixes: #34

ajafff/tsutils,ajafff/tsutils