#4 flipflop patch for ktechlab 0.3.6

[Anonymous]

I noticed that when a switch is pressed or released somewhere in a circuit
with flipflops d or jk, a parasite clock signal (with edge high) is emitted
for each flipflops of the circuit, even if the switch does not make any
changes to the flipflops's entries.
I tried to find why the variable "LogicOut * changed" contains the parasite
clock signals, but it seems to complicated to me (I am new with C++).
Fortunately, I found a simple way to fix the bug without fixing it from the
roots, but at least it works.
This bug needs to be fixed more cleanly.

[Nobody/Anonymous]

The patch