Add .gitignore for npcf.conf
Don't reset deco flags when opening form

This stops the two checkboxes being reset to false every time the form
is opened. They were also being set to booleans, whereas the code uses
strings everywhere else. There is also code added to fix any invalid
boolean values found in saved data, converting them to strings.
Fix deco npc non-owner formspec

I don't know if this was always broken or if minetest has become more
strict, but the 'size' element is required.
Properly remove spawner when used or dug

Using minetest.dig_node causes various issues. An example is that when
area protection is in effect, it fails (even for your own area, because
minetest.dig_node doesn't allow a player to be specfied, it uses a null
one). So in the event of failure, a) after spawning, the spawner stays
there, and b) when you dig it, you get a copy in your inventory (because
the return value from dig_node was ignored) but it stays there so you
can dig infinite amounts of it.

Just using remove_node resolves all this.
Add a tell command
Merge pull request #1 from CiaranG/master

A few little fixes