Increase tolerance of install DHCP
Increase tolerance of install DHCP

For Ubuntu, added the following kernel options:
netcfg/link_detection_timeout=20
netcfg/dhcptimeout=120
For CentOS:
dhcptimeout=120

Closes-Bug: #1381266
Related-Bug: #1376680
Related-Bug: #1379917
blueprint 100-nodes-support

Change-Id: I8bf38ae18b5741b03e6bda5f8e69748a8ecdf2ec

eayunstack/fuel-library,stackforge/fuel-library,SmartInfrastructures/fuel-library-dev,huntxu/fuel-library,zhaochao/fuel-library,eayunstack/fuel-library,SmartInfrastructures/fuel-library-dev,eayunstack/fuel-library,ddepaoli3/fuel-library-dev,stackforge/fuel-library,Metaswitch/fuel-library,huntxu/fuel-library,zhaochao/fuel-library,stackforge/fuel-library,xarses/fuel-library,ddepaoli3/fuel-library-dev,zhaochao/fuel-library,xarses/fuel-library,Metaswitch/fuel-library,ddepaoli3/fuel-library-dev,eayunstack/fuel-library,zhaochao/fuel-library,eayunstack/fuel-library,xarses/fuel-library,ddepaoli3/fuel-library-dev,Metaswitch/fuel-library,xarses/fuel-library,huntxu/fuel-library,ddepaoli3/fuel-library-dev,zhaochao/fuel-library,huntxu/fuel-library,SmartInfrastructures/fuel-library-dev,Metaswitch/fuel-library,SmartInfrastructures/fuel-library-dev,SmartInfrastructures/fuel-library-dev,stackforge/fuel-library,huntxu/fuel-library