Update python scripts to find user's preferred python binary through env.

scripts/bootprog.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 #
 # bootprog.py: STM32 SystemMemory Production Programmer -- version 1.1
 # Copyright (C) 2011  Black Sphere Technologies 

scripts/gdb.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 #
 # gdb.py: Python module for low level GDB protocol implementation
 # Copyright (C) 2009  Black Sphere Technologies

scripts/hexprog.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 
 # hexprog.py: Python application to flash a target with an Intel hex file
 # Copyright (C) 2011  Black Sphere Technologies

scripts/stm32_mem.py

@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/env python
 #
 # stm32_mem.py: STM32 memory access using USB DFU class
 # Copyright (C) 2011  Black Sphere Technologies