Remove unused Sqlb command (this command is duplicated by :!sqlb & exit)

Where sqlb is an alias for sqlitebrowser **/*.sqlite in the shell.
Remove nerdtree CD command

This was removed because it causes latency when using NERDTree's C
command since it's waiting for the possibility of a "D" to follow.
<leader>nt does essentially the same thing as CD which switches NERDTree
to the current directory. Currently <leader>nt is "open NERDTree in the
current directory".
Modify path to search recursively up an down.

I plan to start using the :find command instead of :e **/ because it
allows recursive searching upward and in general because it can be
modified by 'path'.