dirstate-v2: Swap the order of size and mtime on disk This makes the dirstate-v2 file format match dirstate-v1 for the order of `mode`, `size`, and `mtime`. This order does not matter as long as these components are handled through named fields/attributes in code, but in a few places we still have tuples so having the same order everywhere might help avoid a bug that might not be obvious since those components have the same type. Differential Revision: https://phab.mercurial-scm.org/D11620

dirstate-v2: Document flags/mode/size/mtime fields of tree nodes This file format modification was previously left incomplete because of planned upcoming changes. Not all of these changes have been made yet, but documenting what exists today will help talking more widely about it. Differential Revision: https://phab.mercurial-scm.org/D11625

help: update help text for debug-repair-issue6528 The changegroup fix was put in 5.9.1, this is now out of date. Alson, this can maybe encourage people to upgrade? Differential Revision: https://phab.mercurial-scm.org/D11392

dispatch: use detailed exit code 250 for keyboard interrupt Among our users at Google, we're still seeing several percent of commands fail with exit code 255. I suspect keyboard interrupts is an important remaining reason. This is a resend of D10086 with some fixes for pager handling added ahead of it. Differential Revision: https://phab.mercurial-scm.org/D11628