add emphasis to note sections
add git to required packages
add info on using the librenms vm
Add contributing guidelines
Add Observium users welcome
Update README

- Add Observium users welcome
- Add contributing guidelines
- Tidy links
Update CONTRIBUTING.md

Encourage the use of 4-digit issue ids
Update Observium_Welcome.md

Correct revision number
add framework for new cron features; add ability to update librenms daily
update install docs to include notice about daily updates
Merge branch 'master' into wrapper

Conflicts:
	config.php.default
	librenms.cron