add 'use-package-' prefix to 'with-elapsed-timer'

Fixes #35.
fix bind-key URL (fixes #58)

Also makes a start on #32.
Merge pull request #79 from aspiers/best-practices

Start addressing some of @jaalto's submitted issues.
README.md: fix typo and punctuation
stop describe-personal-keybindings adding trailing space

When emacs is configured to highlight trailing whitespace,
the *Personal Keybindings* buffer looked pretty ugly.
This fixes that.
Fix typo
Merge pull request #82 from cmpitg/patch-1

Fix typo
* README.md: Some details about :init
* README.md: Document :demand
Merge remote-tracking branch 'YoungFrog/master'