Add more useful information to templates.

The templates show current commit, the date and the page number. The format is
not the best but these are things I think should be included.
Remove unneeded quoting.
Add info section to note template.
Move to the directory the note is in.

This will allow the vim process to do the right thing when using git commands.
Add an optional title to new.

Whatever new is called with will be used to generate a title for the note. If
nothing is given the '#  #' is used as a place holder.
Info section in template should be h2.
Add xapian env variable
All notes should be in a notes directory.
Add _NOTES_NOTES variable.
Simplify listing notes.
Simpler showing.

Showing is now a shell script. I need to simplify the code in general. This
version is probably much worse than the old one but I would rather start with a
basis like this than the older stuff. In addition, I need to use consitent date
formats. I should probably move the new format to the old nested one.