implemented btfss Instruction (#28)

Co-authored-by: Darkress <30271678+DarkressX@users.noreply.github.com>
Reviewed-on: darkress/pic16f84-sim#28

de/darkress/pic16f84sim/commands/Btfss.java

@@ -0,0 +1,29 @@
+package de.darkress.pic16f84sim.commands;
+
+import de.darkress.pic16f84sim.microcontroller.Memory;
+import de.darkress.pic16f84sim.microcontroller.ProgramCounter;
+
+public class Btfss extends BitOrientedCommandUtils implements Command
+{
+    private final int address;
+    private int bitPlacement;
+
+    public Btfss(int input)
+    {
+        address = input & 0x007F;
+        bitPlacement = checkBitPlacement(input);
+    }
+
+    @Override
+    public void execute()
+    {
+        int result = Memory.getRegister(address);
+
+        if((result & (1 << bitPlacement)) > 0) //Test if bit is set
+        {
+            ProgramCounter.incPC();
+        }
+
+        ProgramCounter.incPC();
+    }
+}