Update quickstart.rst

Fix link, prereqs.html -> prereq.html
add defalt log filter to settings_default.py to get rid of deprecation warning
fix test suite
add examplenode flag to auto-generated settings
New example node: atomic-spectroscopy database stripped down for Chianti-7. Data files (which are tiny) are included.
Merge pull request #120 from guyrixon/master

New example node: "tignanello"
add MinimalNode/ which is a copy of the ExampleNode, stripped from all bells & whistles. useful for tutorial
Merge branch 'master' of github.com:ivh/VAMDC-VALD