[MERGE] Merge branch 'stable-2.12' into stable-2.13

['Petr Pudlak' via ganeti-devel]

commit fbd3cd369a7128799a02564a5582a3af50cc36ec
Merge: 4b41183 14a85a6
Author: Petr Pudlak <pud...@google.com>
Date:   Thu Feb 12 11:29:28 2015 +0100

    Merge branch 'stable-2.12' into stable-2.13
    
    * stable-2.12
      Construct lenses correctly for different 'lens' versions
      Create a simple CPP macro for detecting lens versions
      Allow LVM output parsing to work for thin volumes
    
    * stable-2.11
      (no changes)
    
    * stable-2.10
      Also distribute devel/build_chroot
      Update ganeti download location
      Fix haddock comment
    
    Signed-off-by: Petr Pudlak <pud...@google.com>