return true only when a valid solution found

[Mattolo4]

In simple_IK (i guess incorrectly) returns true (so it succeed) even when the collision check fails to find a valid solution, causing the returned solution to be the initial start position rather than an actual IK solution.

When check_collision=True and hasCollision(q) returns True:

• the solution.position is not updated (collision detected)
• but the function still returns True
• the caller recieves the initial solution value, which in this case is the starting position

So IK appears to be "succeeded" but it returns the starting position as solution. By returning True only when a valid solution is found solves this bug,

[sea-bass]

Oh wow, good catch!