Added org.conman.string.wrapt().

Wraps a string at the given margin (78 by default), returns the results
in a table.
Remove org.conman.string.base64.

I have a separate module for that.
Remove org.conman.trim.

It can be easily replaced with Lua code.
Remove org.conman.string.remchar().

It can be replaced easily with Lua.
Rewrite org.conman.string.wrap() in Lua.