Description of problem:
Crash after selecting one repository entry from the 'repo' section. 

Version-Release number of selected component (if applicable):
v0.99.16 i386 

rpm -qi yumex

How reproducible:


Steps to Reproduce:
1. Click on left pane of buttons to choose 'Repos'
2. On rtpane, choose one repository after deselecting all
3. Click the Refresh button(rtpane)
  
Actual results:
crash report embedded, this didn't happen before

"
Component: yumex
Version: 0.99.16
Summary: TB401f0859 yumexmain.py:893:_runBackground:AttributeError:
YumexMainApplication instance has no attribute 'backgroundThread'

Traceback (most recent call last):
  File "/usr/share/yumex/yumexmain.py", line 905, in ?
    mainApp = YumexMainApplication()
  File "/usr/share/yumex/yumexmain.py", line 471, in __init__
    self.setup_yum()
  File "/usr/share/yumex/yumexmain.py", line 854, in setup_yum
    if self._runBackground( self.yumexbase.load_repo_data, rload ):
  File "/usr/share/yumex/yumexmain.py", line 893, in _runBackground
    while self.backgroundThread.isAlive():
AttributeError: YumexMainApplication instance has no attribute 'backgroundThread'

Local variables in innermost frame:
runfunc: <bound method yumexBase.load_repo_data of <yumex.yumexBase.yumexBase
object at 0xb79e86cc>>
args: (False,)
self: <__main__.YumexMainApplication instance at 0xb79dc2ac>

"