Explain how SHM limitations force us to store the revprop generation in disk and why that code is safe. Docstring improvement only.
Explain how SHM limitations force us to store the revprop generation in disk
and why that code is safe. Docstring improvement only.

* subversion/libsvn_fs_fs/fs_fs.c
  (revprop caching): add technical background info

Suggested by: gstein

git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1345872 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion