sos - fixed behaviour when -a option is used

calling sosreport -a -o postgresql set all the
postgresql plugin options to True which was an
unexpected and unhandled value.

Fixed also some minor issues like wrong indentation,
instance attribute declaration out of __init__,
file built-in redefinition.

Change-Id: Ifcebf02bd96bec18094175d97013bee1c54b5e34
Signed-off-by: Sandro Bonazzola <sbonazzo@redhat.com>