Merge branch 'bp/fsmonitor'

We learned to talk to watchman to speed up "git status" and other
operations that need to see which paths have been modified.

* bp/fsmonitor:
  fsmonitor: preserve utf8 filenames in fsmonitor-watchman log
  fsmonitor: read entirety of watchman output
  fsmonitor: MINGW support for watchman integration
  fsmonitor: add a performance test
  fsmonitor: add a sample integration script for Watchman
  fsmonitor: add test cases for fsmonitor extension
  split-index: disable the fsmonitor extension when running the split index test
  fsmonitor: add a test tool to dump the index extension
  update-index: add fsmonitor support to update-index
  ls-files: Add support in ls-files to display the fsmonitor valid bit
  fsmonitor: add documentation for the fsmonitor extension.
  fsmonitor: teach git to optionally utilize a file system monitor to speed up detecting new or changed files.
  update-index: add a new --force-write-index option
  preload-index: add override to enable testing preload-index
  bswap: add 64 bit endianness helper get_be64

submodule.c

@@ -62,7 +62,7 @@ int is_staging_gitmodules_ok(const struct index_state *istate)
 	if ((pos >= 0) && (pos < istate->cache_nr)) {
 		struct stat st;
 		if (lstat(GITMODULES_FILE, &st) == 0 &&
-		    ce_match_stat(istate->cache[pos], &st, 0) & DATA_CHANGED)
+		    ce_match_stat(istate->cache[pos], &st, CE_MATCH_IGNORE_FSMONITOR) & DATA_CHANGED)
 			return 0;
 	}