esp8266: Explicitly collect garbage in bootstrap scripts.

Leads to less fragmentation at teh time user code starts.

esp8266/scripts/inisetup.py

@@ -40,7 +40,9 @@ def setup():
     with open("/boot.py", "w") as f:
         f.write("""\
 # This file is executed on every boot (including wake-boot from deepsleep)
+import gc
 #import webrepl
 #webrepl.start()
+gc.collect()
 """)
     return vfs