Fixes #372

Before attempting to send mail, the hostname is retrieved using
socket.gethostname. If the hostname includes 'microbio.me', then mail is sent.
Otherwise, the user is dumped back to the portal with a message stating that
mail can be sent only from the microbio.me domain.
Merge branch 'master' of https://github.com/qiime/qiime_web_app into i372
Add function can_send_mail

takes no arguments, returns true if 'microbio.me' is in socket.hostname();
returns false otherwise
Adding doc string and streamlined fn
Modify files to use can_send_mail

Files should use can_send_mail from utils.mail instead of explicitly checking
whether or not 'microbio.me' appears in socket.hostname() return value
Renaming field is_7_to_13 to juvenile_age
Fixes #315

- Change "Is 7 to 13" checkbox to radio buttons
- Modify some logic on survey_main to use new checkbox name
- Modify JS to validate new radio buttons
- Add age into AGJUVENILE emails so we know which consent form to send them
Fixing tabindex on radio button
Remove juvenile age from subject line

The radio buttons' values are now simple english phrases that are included
in the body of the email.
Merge branch 'master' of https://github.com/qiime/qiime_web_app into i315

Conflicts:
	www/americangut/new_participant.psp
barcode util updated. see the ticket #446 on github
added link to the full instructions
Merge branch 'master' of https://github.com/qiime/qiime_web_app into i372

Conflicts:
	www/americangut/submit_human_survey.psp
Merge pull request #2 from meganap/portal_redesign

Portal redesign
Add alert message for survey editing

- Add javascript function that raises an alert message before submitting the
form
- Change link on participan_overview to call that javascript function
Merge pull request #479 from adamrp/i286

Add alert message for survey editing
more barcodes
Merge pull request #480 from wasade/new_bcs

more barcodes
Merge pull request #458 from adamrp/i315

I315
Merge pull request #468 from wasade/full_instructions

added link to the full instructions