revlog: calculate base revisions iteratively This is in preparation for generaldelta, where the revlog entry base field is reinterpreted as the deltaparent. For that reason we also rename the base function to chainbase. Without generaldelta, performance is unaffected, but generaldelta will suffer from this in _addrevision, since delta chains will be walked repeatedly. A cache has been added to eliminate this problem completely.

revlog: remove the last bits of punched/shallow Most of it was removed in e7483ec3c374, but a few pieces were accidentally left behind.

util: make readfile() operate in binary mode writefile() and appendfile() are already working that way.

cmdutil: normalize log message eols when reading from file This will be necessary once util.readfile() operates in binary mode. While changelog.add() already normalizes the message, doing so in logmessage() is required as ui.edit() or others expect messages with LF only.

match: make 'listfile:' split on LF and CRLF We want util.readfile() to operate in binary mode, so EOLs have to be handled correctly depending on the platform. It seems both easier and more convenient to treat LF and CRLF the same way on all platforms.

progress: remove useless statement left by bab267e7fc1a