eol: added filter aliases for backwards compatibility with win32text

This makes it possible to switch most win32text configurations (i.e. those
that use cleverencode and cleverdecode) to hgeol simply by disabling one and
enabling the other. Any rules found in repo-specific .hgeol files will be
appended to the configuration in .hgrc.

hgext/eol.py

@@ -104,6 +104,9 b' filters = {'
     'to-lf': tolf,
     'to-crlf': tocrlf,
     'is-binary': isbinary,
+    # The following provide backwards compatibility with win32text
+    'cleverencode': tolf,
+    'cleverdecode': tocrlf
 }