Err255

[papajoker]

in install base and install DE
redirect pacman output in log file, and show only if we have error 255 after error dialog

one test result :

                                              Error ───────────┐
                                   │                           │  
                                   │ [install basepkgs][255]   │  
                                   ├───────────────────────────┤  
                                   │       <Accepter>          │  
                                   └───────────────────────────┘  
                                     ┌──── Install Base ──────┐
                                     │                        │  
                                     │ Installation failed.   │  
                                     │                        │  
                                     ├────────────────────────┤  
                                     │       <Accepter>       │  
                                     └────────────────────────┘  

==> Creating install root at /mnt
  -> Installing packages to /mnt
:: Synchronizing package databases...
error: failed to update core (unable to lock database)
error: failed to update extra (unable to lock database)
error: failed to update community (unable to lock database)
error: failed to update multilib (unable to lock database)
error: failed to synchronize any databases
error: failed to init transaction (unable to lock database)
error: could not lock database: File exists
  if you're sure a package manager is not already
  running, you can remove /mnt/var/lib/pacman/db.lck
==> ERROR: Failed to install packages to new root