rustdoc: add crate level doc

Contains a link to the 'backup' module's doc, as that explains a lot
about the inner workings of PBS and probably marks a good entry point
for new readers.

Signed-off-by: Stefan Reiter <s.reiter@proxmox.com>

diff --git a/src/lib.rs b/src/lib.rs
index c44c9ae195ed2f8301ade1316b324892d7093e18..cc51b2e0c8d8793a9e99421c517082730ff95d3c 100644 (file)
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,3 +1,8 @@
+//! See the different modules for documentation on their usage.
+//!
+//! The [backup](backup/index.html) module contains some detailed information
+//! on the inner workings of the backup server regarding data storage.
+
 pub mod task;
 
 #[macro_use]