switching flag order for jekyll
1.  Modifying home page validator to make sure that the contact address *isn't* 'admin@software-carpentry.org'.
2.  Adding tests for validator's checking of helpers list.
Making instructions for checking bootcamp home pages more prominent
Merge pull request #554 from gvwilson/checking-contact-email-address

Checking that contact email address has been re-set in index.html
Merge pull request #518 from drlabratory/jekyll-flags

switch order of jekyll flags in Makefile
Merge pull request #565 from gvwilson/making-check-more-prominent

Making instructions for checking bootcamp home pages more prominent