Description of problem:
POST_UP_SCRIPT requires space after '=' in /etc/sysconfig/network-scripts/ifcfg-xxx


How reproducible:


Steps to Reproduce:
1. add 'POST_UP_SCRIPT=echo Hello' to /etc/sysconfig/network-scripts/ifcfg-eth0
2. run ifup eth0
3. An error message 'Hello: command not found" will be displayed.
4. change 'POST_UP_SCRIPT=echo Hello' to 'POST_UP_SCRIPT= echo Hello' (adding a space after '=')
  
Actual results:
The error message 'Hello: command not found" is printed on the screen.

Expected results:
The Text 'Hello' is printed on the screen.

Additional info:
If you change 'POST_UP_SCRIPT=echo Hello' to 'POST_UP_SCRIPT= echo Hello' (adding a space after '=') it will work fine.