Drop .py extension from the unittest script

MANIFEST

@@ -9,4 +9,4 @@ archivemail.1
 archivemail.sgml
 examples/archivemail_all
 setup.py
-test_archivemail.py
+test_archivemail

Makefile

@@ -12,7 +12,7 @@ clean:
 	rm -rf $(HTDOCS)
 
 test:
-	python test_archivemail.py
+	python test_archivemail
 
 clobber: clean
 	rm -rf build dist

README

@@ -36,7 +36,7 @@ INSTALLATION:
 
 If you want to test archivemail:
     cp archivemail archivemail.py
-    python test_archivemail.py
+    python test_archivemail
     (NOTE: This could take over 90 seconds on slower systems)
 
 To install archivemail, run:

TODO

@@ -110,7 +110,7 @@ run. Better to fail gracefully and keep going.
 Think about the best way to specify the names of archives created with
 possibly an --archive-name option.
 
-Add more tests (see top of test_archivemail.py)
+Add more tests (see top of test_archivemail)
 
 We need some better checking to see if we are really looking at a valid
 mbox-format mailbox.