Make calls to logs.setup() explicit in each cmd.

Further reducing magic implicit behaviour to make code easier to
follow.

redo/cmd_stamp.py

@@ -1,18 +1,21 @@
 import sys, os
-from . import env, state
-from .logs import err, debug2
+from . import env, logs, state
+from .logs import debug2
 
 
 def main():
-    env.inherit()
     if len(sys.argv) > 1:
-        err('%s: no arguments expected.\n' % sys.argv[0])
+        sys.stderr.write('%s: no arguments expected.\n' % sys.argv[0])
         sys.exit(1)
 
     if os.isatty(0):
-        err('%s: you must provide the data to stamp on stdin\n' % sys.argv[0])
+        sys.stderr.write('%s: you must provide the data to stamp on stdin\n'
+                         % sys.argv[0])
         sys.exit(1)
 
+    env.inherit()
+    logs.setup(tty=sys.stderr, pretty=env.v.PRETTY, color=env.v.COLOR)
+
     # hashlib is only available in python 2.5 or higher, but the 'sha'
     # module produces a DeprecationWarning in python 2.6 or higher.  We want
     # to support python 2.4 and above without any stupid warnings, so let's