[MigrationResults] collect info about conversions and upgrades

[bvassova]

A new tiny plugin independent on leapp and convert2rhel is proposed.

It should collect /etc/migration-results with info about RHEL
conversions and upgrades, whenever the file is present.

Resolves: #2631
Related: #2627
Relevant to: rhbz#1959598

Signed-off-by: Barbora Vassova bvassova@redhat.com

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[pmoravec]

This needs to be in the

"""Information about conversions and upgrades"""

comment style - compare it with other plugins. short_desc works well since 4.0, until then you get:

# sosreport -l

..
The following plugins are currently disabled:

..
 memcached            inactive       memcached distributed memory caching system
 migration_results    inactive       This is the base class for sosreport plugins. Plugins should subclass
    this and set the class variables where applicable.

    plugin_name is a string returned by plugin.name(). If this is set to None
    (the default) class\_.__name__.tolower() will be returned. Be sure to set
    ..
 mongodb              inactive       MongoDB document database