add merge command. means same thing as "update -m".
repo.addchangegroup method now returns number of heads modified and added,
so command line can tell whether update or merge needed. this makes
tiny change to ssh wire protocol, but change is backwards compatible.
pull command now returns 0 if no changes to pull.
1:f248da0d4c3e
0:9eca13a34789
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9eca13a34789
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merge: warning: conflicts during merge
merging file1
merging file1 failed!
diff -r f248da0d4c3e file1
--- a/file1
+++ b/file1
@@ -1,3 +1,7 @@ added file1
added file1
another line of text
+<<<<<<<
+changed file1 different
+=======
changed file1
+>>>>>>>
M file1
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