python: Move more code into m5.util allow SCons to use that code.

Get rid of misc.py and just stick misc things in __init__.py
Move utility functions out of SCons files and into m5.util
Move utility type stuff from m5/__init__.py to m5/util/__init__.py
Remove buildEnv from m5 and allow access only from m5.defines
Rename AddToPath to addToPath while we're moving it to m5.util
Rename read_command to readCommand while we're moving it
Rename compare_versions to compareVersions while we're moving it.

--HG--
rename : src/python/m5/convert.py => src/python/m5/util/convert.py
rename : src/python/m5/smartdict.py => src/python/m5/util/smartdict.py

src/python/m5/trace.py

@@ -48,5 +48,5 @@ def help():
         if flag == 'All':
             continue
         print "    %s: %s" % (flag, flags.descriptions[flag])
-        util.print_list(flags.compoundMap[flag], indent=8)
+        util.printList(flags.compoundMap[flag], indent=8)
         print