add dev notes

DEVELOPMENT.md

@@ -0,0 +1,24 @@
+# DEVELOPMENT NOTES
+
+## archiving old versions
+
+(hopefully automated someday)
+
+1. make repo on github
+2. in threejsfundamentals.org
+   1. git fetch origin gh-pages
+   2. git checkout gh-pages
+   3. git rebase origin/gh-pages?
+   4. git clone --branch gh-pages ../old.threejsfundamentals/rXXX
+3. cd ../old.threejsfundamentals.rXXX
+4. git remote rm origin
+5. git remote add origin <new-github-repo>
+6. edit CNAME
+7. delete 
+   * robots.txt
+   * sitemap.xml
+   * atom.xml
+   * Gruntfile.js
+8. s/\/threejsfundamentals.org/\/rXXX.threejsfundamentals.org/g
+9. git push -u origin gh-pages
+10. Update DNS (cloudflare)