Simplify naming

The idea of reusing the "stone" from the name was
clever, but it has some drawbacks.

- It doesn't fit in with NodeCore's generally purely
  concatenative naming scheme, where adjectives
  are prepended to general names for things.
- It would make translations (or just general
  understanding) more difficult for non-native
  speakers.
- It's a little weird separating certain words, like
  tarstone and cloudstone, because "tar" and
  "cloud" appearing on their own now seem to
  imply that that material is somehow used in the
  composition of the go stones.

Having all of the stones have "go" in their name
also reinforces that these pieces are meant to be
part of a logical set, used together, and are meant
to be used for the game of go (in case somebody
sees one in isolation and doesn't know what it's
from).

It also makes it easier to just search for "go" in
szutil_givemenu and find all the go stones;
searching for "stone" yields too many results.

stones.lua

@@ -14,17 +14,7 @@ local function reg(name, basename, basedef)
     if minetest.registered_nodes[piecename] then return end
     local desc = basedef.description or name
 
-    local nodeDesc
-
-    local nameStone = string.match(desc, "(.*)stone$")
-    if nameStone then
-        nodeDesc = nameStone
-    elseif desc == "Stone" then
-        nodeDesc = "Go"
-    else
-        nodeDesc = desc
-    end
-    nodeDesc = nodeDesc .. " Stone"
+    local nodeDesc = desc .. " Go Stone"
 
     minetest.register_node(":" .. piecename, {
         description = nodeDesc,