Add DEFAULT NULL statement to silence check_db script.
Consistently capitalize "DEFAULT" and "AUTO_INCREMENT" SQL keywords,
add explicit "DEFAULT NULL" statements where implicitly assumed.

No functional changes.
Revert part of previous commit: don't use DEFAULT NULL for longblob
and longtext types, since this also not output by MySQL.
Rename SQL upgrade files to current version numbers and
add previous minor version SQL upgrade files.
Update new meaning of lazy_eval_results configuration variable
since 3.4, see also commits a64266bb and 29634b4b.
Remove boost::lexical_cast dependency.
Fix DOS newlines and wrong bound in checktestdata tests.
sudoers file is needed for judgehost, not domserver
Remove team_select configuration option: always enabled.
Fix check of problemtext type (not during upload).
Small HTML improvements.
Use link that points to the 3-letter country code variants.

iso.org doesn't make those publically available.
Add missing $pagename
Various HTML validity fixes
Replace align attribute with proper CSS.
Upgrade to HTML5.

As with Javascript, I believe we should use its functions only
where they provide added comfort but are not essential to core
functionality, as long as there are browsers (IE) which lack
support.
allow to specify extra form attributes
Make use of HTML5 for basic form validation.

More to follow.
Add checker for judgehost.
Add more HTML5 client side form validation.