added config for w3m

uses a decent mailer and editor, and stop asking for confirmation to quit
renamed w3m-config to dot.w3m

I like the name-style dot.*, easier to read and factorise in Makefile
ignore w3m history
added README.md
fixed sort preference in muttrc
added a separate file for contacts
refactored Makefile to make install easier

By using a function, we can install any directory with a single line
faster reply in mutt, less useless confirmations
use smtps by default