revlog: fix index computation during inline->non-inline transition The computation in 63edc384d3b7 failed to factor in the index entries themselve as revlog.start() doesn't count them. Found by Valtenin Gatienbaron with a more precise test case from me. Differential Revision: https://phab.mercurial-scm.org/D10724

dirstate-v2: Change the on-disk format to be tree-shaped Nodes are stored not only for tracked files but also for their ancestor directories. A node has "pointers" (byte count from the start of the file) to its direct child nodes. Everything can be accessed with zero copy. Differential Revision: https://phab.mercurial-scm.org/D10722