made several changes to guides to comply to doc conventions

“Speed not required” is not a sentence
Gb should be GB
added a , after floating IPs
fixed sentence around “To implement a true multi-node test of Swift
since it did not make sense
removed extra underline line after Machines
removed capitalization of service names to comply with docs conventions
https://wiki.openstack.org/wiki/Documentation/Conventions
changed to DevStack for consistency throughout
Change-Id: I531bf6b2bad62fbf9d1417b2b1ce06de3715e0f0
diff --git a/doc/source/guides/devstack-with-nested-kvm.rst b/doc/source/guides/devstack-with-nested-kvm.rst
index 610300b..b35492e 100644
--- a/doc/source/guides/devstack-with-nested-kvm.rst
+++ b/doc/source/guides/devstack-with-nested-kvm.rst
@@ -54,7 +54,7 @@
 
 
 Configure Nested KVM for AMD-based Machines
---------------------------------------------
+-------------------------------------------
 
 Procedure to enable nested KVM virtualization on AMD-based machines.
 
@@ -121,7 +121,7 @@
 back to `virt_type=qemu`, i.e. plain QEMU emulation.
 
 Optionally, to explicitly set the type of virtualization, to KVM, by the
-libvirt driver in Nova, the below config attribute can be used in
+libvirt driver in nova, the below config attribute can be used in
 DevStack's ``local.conf``:
 
 ::