Disable file indexing on VMs

Some machines while working keeps high level of CPU and IO usage because file indexing, which really should be disabled.

I have seen baloo takin 170% of cpu power (200% max) on this:
LinuxopenSUSE_42_3x86_64LinuxopenSUSE_42_3x86_64GCCqtci-linux-openSUSE-42.3-x86_64-

but other systems have similar functionality.