thanks to Alexander Ufimtsev and mcarbone for the review.

Changelog:
- #178915 Always add a query string in hook_exit() if there are session messages to be shown (kudos to Barry Jaspan).
- Added Barry Jaspan to the credits in README.txt.

Corrected handling of 403/404 errors in relation to cached file creation (kudos to Barry Jaspan for the patch).

- #153179 Patched for Drupal 5.x compatibility, corrected front page handling, and added expiration time to the Boost page footer (kudos to Alexander I. Grafov, Jacob Peddicord and Justin Miller).
- #103884 Updated the Boost .htaccess file from Drupal 5.x-dev; also added HTTP headers and special-case mod_rewrite rules for correctly handling caching of the front page (kudos to Axel).
- Imported the default .htaccess file from Drupal 5.x-dev.
- Updated credits listing in README.txt.
- Updated INSTALL.txt instructions to reflect Drupal 5.x.

Changelog:
- #153179 Backported corrected front page handling and Boost page footer expiration time from 5.x branch (kudos to Axel).
- #103884 Backported .htaccess improvements from 5.x branch (kudos to Axel).
- Updated credits listing in README.txt.

Added code for module weight update to the install hook to ensure Boost is loaded early on in the Drupal bootstrap.

Added a hook_exit() handler to ensure session messages set on form submission will get shown on the next page despite that page having been cached by Boost.

Refactored recursive file expiry to avoid spurious watchdog warnings on non-empty directories (fixes #99646).

Documented the FollowSymLinks requirement and added note about using the HTML footer to determine whether a page response was dynamically generated or not.

Removed realpath() calls from symlink creation as they were causing different behavior on BSD vs Linux.