Create minetest.xml

Tested on Chakra 2014.02 "Curie", Minetest 0.4.9
After a few weeks of using minetest, this cleaner erased:
  Cache: 39.0 MiB
  Debug logs: 595.4 MiB
  Favorite server list: 828 B
  Total: 634.4 MiB
(Mod settings & Mods will vary greatly depending on the user, so they aren't included in above stats)
home page: http://www.minetest.net/
Popularity stats: Currently has roughly 30 public servers: http://servers.minetest.net/
Merge pull request #26 from tiemay/patch-1

Create minetest.xml
Remove mod settings option

Deleting ~/.minetest/worlds/*/world.mt will break a world if it uses a game other then minetest or a back end other then sqlight3 (the defaults).
Merge pull request #27 from tiemay/patch-2

Remove mod settings option
Update copyright year
Merge pull request #28 from tiemay/patch-3

Update copyright year
Added warning

It kinda dawned on me after using BB on multiple machines that it would be wise to warn users about their passwords getting deleted.
clarify what mods option does

Currently, no matter how you remove a mod, any blocks or items from the mod in a world will become 'unknown' after removing or disabling the mod; This cleaner does not remedy this issue.
Add alternative file path

Chakra 2014.02 has ~/.config/VirtualBox
Merge pull request #30 from tiemay/patch-2

Add alternative file path
Merge pull request #29 from tiemay/patch-1

clarify what mods option does
VirtualBox: match .log without .log.1-style numbered version (issue #31)