commit 168d1ebd8886f7c70bc4484a0f3783451862ac25
Author: Alon Bar-Lev <alonbl>
Date:   Tue Sep 18 22:46:17 2012 +0300

    bootstrap: use yum API
    
    PREVIOUS IMPLEMENTATION
    
    Use of yum command-line to automate package installation.
    
    Install package almost one by once, so valid status can be reported to
    master.
    
    PROBLEMS IN PREVIOUS IMPLEMENTATION
    
     - As each package was installed separately, conflicts could not be
       resolved.
    
     - Dependency list should have been maintained, to match dependencies'
       changes over time.
    
     - Alternate packages, or any alternate dependency trees should have
       been maintained separately.
    
     - Each execution of yum recalculate the cache, mirrors and
       dependencies, this took time.
    
     - If another instance is running, yum waits for ever.
    
    NEW IMPLEMENTATION
    
    Use the yum python API, use single transaction, only top-level
    components, proper logging.
    
    This implementation resolves all the issue of previous implementation.
    
    Also removing the architecture specific package naming.
    
    PROBLEMS IN NEW IMPLEMENTATION
    
    As it turns out, the yum API is not exactly pure API, it needs a lot
    more work especially at log interface, as its lazy use of logs and
    direct print of messages to stdout/stderr is not something that is
    expected from an API.
    
    The new implementation applies workarounds to these issues, for now we
    are good.
    
    CLEANUP
    
    As the vdsm-bootstrap package is to be installed on older engines,
    legacy code could not have been removed. The usage of yum from
    deployUtils, and the installation functions from the vds_bootstrap.py
    could have been removed, ~340 lines of code.
    
    Change-Id: I65796801bc2db7c5abf71c1e9e4ad8ca308138b9
    Signed-off-by: Alon Bar-Lev <alonbl>
    Reviewed-on: http://gerrit.ovirt.org/8039
    Reviewed-by: Dan Kenigsberg <danken>