revlog: add punched revision flag
index flag to identify a revision as punched, i.e. it contains no data.
REVIDX_PUNCHED_FLAG = 2, is used to mark a revision as punched.
REVIDX_KNOWN_FLAGS is the accumulation of all index flags.
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Some stuff to ponder very carefully.
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Copyright 2046, The Masters
Some stuff to ponder very carefully.
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% Problem encoding:
abort: missing header "Copyright 2046, The Masters" in morestuff.txt
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