Description of problem:
Editing proxy ignore-hosts setting adds spaces to each element in the list, so setting doesn't work.

Version-Release number of selected component (if applicable):
control-center-3.8.3-2.fc19.x86_64

How reproducible:
Always.

Steps to Reproduce:
1. $ gsettings reset org.gnome.system.proxy ignore-hosts 
2. $ gsettings get org.gnome.system.proxy ignore-hosts 
['localhost', '127.0.0.0/8', '::1']
3. $ gnome-control-center network
Go to proxy settings and add "*.example.com".
4. $ gsettings get org.gnome.system.proxy ignore-hosts 
['localhost', ' 127.0.0.0/8', ' ::1', ' *.example.com']

Actual results:
$ gsettings get org.gnome.system.proxy ignore-hosts 
['localhost', ' 127.0.0.0/8', ' ::1', ' *.example.com']

Expected results:
$ gsettings get org.gnome.system.proxy ignore-hosts 
['localhost', '127.0.0.0/8', '::1', '*.example.com']