Remove PYTHONPATH requirement to execute run_slave.py.

slave/Makefile

Index: slave/Makefile
diff --git a/slave/Makefile b/slave/Makefile
index 14753edbaa4ac9176a6073b208d3dc850bcdacbd..539c8a0dcafb498e1887199a7d074ae57952aa0a 100644
--- a/slave/Makefile
+++ b/slave/Makefile
@@ -4,10 +4,6 @@
 # directory (next to the buildbot.tac file). It allows you to start/stop the
 # master or slave by doing 'make start' or 'make stop'.
 
-# The 'reconfig' target will tell a buildmaster to reload its config file.
-
-# Note that a relative PYTHONPATH entry is relative to the current directory.
-
 # On the Mac, the buildbot is started via the launchd mechanism as a
 # LaunchAgent to give the slave a proper Mac UI environment for tests.  In
 # order for this to work, the plist must be present and loaded by launchd, and
@@ -28,8 +24,6 @@ USE_LAUNCHD := \
           [ "$$(pwd -P)" = "/b/build/slave" ] && \
           echo 1)
 
-export PYTHONPATH=../third_party/buildbot_7_12:../third_party/twisted_8_1
-
 start:
 ifneq ($(USE_LAUNCHD),1)
 	python run_slave.py --no_save -y buildbot.tac