A combination of fixes and new features for fruitstrap.

* Ability to pass command-line arguments to the running application.
* Fiddled with the device support path discovery so that it works for me with XCode 4.3 on Lion.
* Fixed some bugs with write_gdb_prep_cmds (the string replace on dcp_noprivate with an incorrect length lead to a frequent crash).
* Fill in address.sun_len to make a warning go away.
* Handled gdb exiting slightly more gracefully.
* Closed device control sessions when we don't need them.  These sessions timing out lead to frequent failures the next time they were used.
* Added some getopt argument parsing.
* Added verbose and timeout (timeout for connecting to device) arguments.

demo.c

@@ -1,5 +1,9 @@
 #include <stdio.h>
 
-int main() {
+int main(int argc, const char* argv[]) {
+    int i;
+    for (i = 0; i < argc; i++) {
+        printf("argv[%d] = %s\n", i, argv[i]);
+    }
     return 0;
-}
+}