Implement C and G commands

Pretty straightforward.  copy_ram_to_flash is a simple binding for the C
command, and go is a binding for G that defaults to address 0 and mode
b"T".

alpaca_isp/__init__.py

@@ -168,7 +168,7 @@ class LPC:
 
     def write_ram(self, start, data, count=None):
         """Write count bytes from data to RAM at the given start address
-        
+
         Start and count must be multiples of four.  If count is not specified,
         len(data) is used.
         """
@@ -199,6 +199,24 @@ class LPC:
             end = start
         self._send_command("P {} {}\r\n".format(start, end).encode("utf-8"))
 
+    def copy_ram_to_flash(self, flash, ram, count):
+        """Copy count bytes from RAM to flash
+
+        The flash address should be a 64 byte boundary.  Count should be a
+        power of two in [64, 1024].
+        """
+        self._send_command("C {} {} {}\r\n".format(flash, ram, count).encode(
+            "utf-8"))
+
+    def go(self, address=0, mode=b"T"):
+        """Jump to the given address, in the given mode of execution
+
+        Of course, this function generally causes the ISP command handler to
+        stop running, so it is typically appropriate to follow this with a call
+        to LPC.close.
+        """
+        self._writeline("G {} {}\r\n".format(address, mode).encode("utf-8"))
+
 
 class ReturnCode(Enum):
     """LPC ISP return codes