5046 finetune restic params

docs/30_Configuration/30_Filetransfer.md

@@ -114,11 +114,16 @@ If your /root partition has a limited size and/ or you have a lot of files
 
 `restic_cachedir = [full path]`
 
-The default verbose of IML backup for restic is 2. During file transfer
-this shows unchanged/ new/ deleted files. Change it to a less value
-to generate less log data.
+Restic by default stores file indexes locally. To save space in `restic_cachedir`
+you can disable the file index but the backup will run much slower.
 
-`restic_verbose = 2`
+`restic_nochache = false`
+
+The default verbose of IML backup for restic is 0. 
+If you want to see unchanged/ new/ deleted files set it to "2". But This generates
+larger logs in [installdir]/logs/.
+
+`restic_verbose = 0`
 
 A file transfer can be tagged. Each restic backup gets a defined tag
 
@@ -167,8 +172,11 @@ is a full backup and all following runs make an incremental backup.
 You have the possibility to keep all younger backups and have the possibility to delete
 older backups but to keep N weekly, monthly and yearly snapshots.
 
+The value for "keep-last" never deletes the last N most recent snapshots.
+
 ```text
 # prune 
+restic_keep-last = 5
 restic_keep-hourly = 100
 restic_keep-daily = 90
 restic_keep-weekly = 12