Updated XML file for ARM
Updated XML file for ARM

1. added new xml tag <ARMStorageAccount>
2. added new xml tag <ARMInstanceSize> (There is VM size compatibility
conflict between ARM and ASM. Hence this new tag is added to
differentiate VM sizes.)
3. updated network test definitions.

v-sirebb/azure-linux-automation,v-sirebb/azure-linux-automation,Nidylei/azure-linux-automation,FreeBSDonHyper-V/azure-freebsd-automation,v-sirebb/azure-linux-automation,Nidylei/azure-linux-automation,konkasoftci/azure-linux-automation,hglkrijger/azure-linux-automation,hglkrijger/azure-linux-automation,FreeBSDonHyper-V/azure-freebsd-automation,FreeBSDonHyper-V/azure-freebsd-automation,Nidylei/azure-linux-automation,konkasoftci/azure-linux-automation,konkasoftci/azure-linux-automation,iamshital/azure-linux-automation,iamshital/azure-linux-automation,iamshital/azure-linux-automation,hglkrijger/azure-linux-automation