Reduce number of categories

plugins/virtualization/kvm_cpu

@@ -25,7 +25,7 @@ def config(vm_names):
 
     base_config = """graph_title KVM Virtual Machine CPU usage
 graph_vlabel %%
-graph_category KVM
+graph_category Virtualization
 graph_scale no
 graph_period second
 graph_info This graph shows the current CPU used by virtual machines

plugins/virtualization/kvm_io

@@ -23,7 +23,7 @@ def config(vm_names):
     '''
     base_config = """graph_title KVM Virtual Machine IO usage
 graph_vlabel Bytes read(-)/written(+) per second
-graph_category KVM
+graph_category Virtualization
 graph_info This graph shows the block device I/O used of virtual machines
 graph_args --base 1024
     """

plugins/virtualization/kvm_mem

@@ -23,7 +23,7 @@ def config(vm_names):
     '''
     base_config = """graph_title KVM Virtual Machine Memory usage
 graph_vlabel Bytes
-graph_category KVM
+graph_category Virtualization
 graph_info This graph shows the current amount of memory used by virtual machines
 graph_args --base 1024
     """

plugins/virtualization/kvm_net

@@ -24,7 +24,7 @@ def config(vm_names):
     '''
     base_config = """graph_title KVM Network I/O
 graph_vlabel Bytes rx(-)/tx(+) per second
-graph_category KVM
+graph_category Virtualization
 graph_info This graph shows the network I/O of the virtual machines
 graph_args --base 1024
     """

plugins/virtualization/munin-libvirtpy

@@ -37,7 +37,7 @@ if len(sys.argv) == 2:
         print "graph_title KVM Domain CPU Utilization"
         print "graph_vlabel CPU use in seconds"
         print "graph_args --base 1000"
-        print "graph_category kvm"
+        print "graph_category Virtualization"
 
         for id in ids:
             dom = conn.lookupByID(id)