templater: ignore orig/rej files

If your mercurial/templates/ directory is dirty, then the template system would
otherwise import duplicate templates from the .orig files and potentially try to
parse .rej files.

Since editing/reverting these templates isn't an unexpected action, and since
they're in .hgignore, it's best that the template system know to skip them."

mercurial/templater.py

@@ -891,6 +891,8 b' def stylelist():'
     stylelist = []
     for file in dirlist:
         split = file.split(".")
+        if split[-1] in ('orig', 'rej'):
+            continue
         if split[0] == "map-cmdline":
             stylelist.append(split[1])
     return ", ".join(sorted(stylelist))