Fix missing org name (short and long) in email templates

[bmispelon]

I noticed that the signature of the application notification emails was off:

Kind Regards,
The  Team

--

http://example.com

While investigating I found out that the base.html email template was using org_long_name instead of ORG_LONG_NAME (which is what the global_vars context processor is providing).
This issue appears to be widespread, and it's not helped by the fact that some emails correctly receive the org_long_name variable (it's passed manually in the context).

For this PR, I went with the exhaustive approach of replacing every single instance of org_long_name, org_short_name, and org_email with their uppercase counterparts:

git grep -lw org_long_name | xargs sed -i 's/\borg_long_name\b/ORG_LONG_NAME/'
git grep -lw org_short_name | xargs sed -i 's/\borg_short_name\b/ORG_SHORT_NAME/'
git grep -lw org_email | xargs sed -i 's/\borg_email\b/ORG_EMAIL/'

[bmispelon]

I just realized this breaks compilemessages because it introduces duplicate message definitions. Converting this PR to draft while I figure out how to fix that.

Edit: I ended up fixing the duplicate messages manually by opening the po files with poedit and letting it clean them up.

[wes-otf]

Hey this looks good, thanks for putting it up! I think I'm going to open another PR after merging this that'll automatically add the global_vars context to Markdown emails too so we can toss a lot of that context code, gets redundant.