Add "dump" and "page" commands to CLI usage

Signed-off-by: Lewis Marshall <lewis@lmars.net>

cmd/bolt/main.go

@@ -127,8 +127,10 @@ The commands are:
     bench       run synthetic benchmark against bolt
     check       verifies integrity of bolt database
     compact     copies a bolt database, compacting it in the process
+    dump        print a hexidecimal dump of a single page
     info        print basic info
     help        print this screen
+    page        print one or more pages in human readable format
     pages       print list of pages with their types
     stats       iterate over all pages and generate usage stats