hgmerge: fix diff+patch detection; cleanups
Details:
- actually show help message when no tools are found
- whitespace cleanup (stupid emacs)
- quote more variables
- simplify merge/diff3 error handling
1:f4d7a8c73d23
0:232e179b3f29
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232e179b3f29
232e179b3f29+
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merge: warning: conflicts during merge
merging file1
merging file1 failed!
diff -r f4d7a8c73d23 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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