Rewrite how to build the documentation

And add build script
Add rst2pdf builder
Many other fixes

Closes-Bug: 1282556
Change-Id: I4083495db0b04b8751a397dffd06941a214722c1
Merge "Rewrite how to build the documentation"
Fixing circular imports of NetworkManager

Closes-Bug: #1301814

Change-Id: I7fbd8aedd32f148022aa3bca1188fb4bec91bca8
Merge "Fixing circular imports of NetworkManager"
vCenter integration UI added
removed kvm and qemu hypervisors for custom CentOS release
changed the vcenter UI, added dependencies, removed separate release
vcenter integration UI refactored