Don't use short open tags

They are deprecated and disabled by default. However, the form <?= is
always recognized from PHP 5.4.
Mandate UTF-8 in README
Fix some comments
Don't access translation database during installation

It doesn't exist yet!
"Choose a Member ID" during registration

People are often confused what to type here
Remove short open tags from info pages
Fix conditional statement that disabled i18n

I don't fully understand what was wrong with the previous one.
Update instructions for installing pecl_http and locales
replace_tags: "Click here for directory"