Apache2::Reload reloads modules that change on the disk.

When Perl pulls a file via require, it stores the filename in the global hash %INC. The next time Perl tries to require the same file, it sees the file in %INC and does not reload from disk. This module's handler can be configured to iterate over the modules in %INC and reload those that have changed on disk or only specific modules that have registered themselves with Apache2::Reload. It can also do the check for modified modules, when a special touch-file has been modified.