Attempt to prevent title text overlapping with the header image (though second line sits behind the menu...)

This is required because Flask is forcing (via 301) / to be appended to the url
which previously resulted in no rule matching legacy pages. We could disable
strict_slashes to fix this, but it might cause issues elsewhere.

This is required because "site/" was removed from the urls, but a little backend
trickery is usually necessary to get the urls looking right ^_^

This increases the speed of the site by not requiring the site and blog code to
be imported on every request - just those that are relevant. It also splits the
code into modules which are easier to work with.

It seems that Werkzeug doesn't get confused between /en/blog/ and /en/<path:page>

AFAICT these attributes are meant to be on <link> tags, but it shouldn't hurt
having them here instead (though if it doesn't help and <link> tags need to be
added, then this commit should probably be reverted).

Keep the current website's title for the front page (to help keep its existing page rank for "anonymous network")

Tweaked mirror code so mirror urls can contain the current I2P version, added Launchpad as HTTPS mirror

NOTE: this enables mirrors that require a version string to download the current version
of files. Older file versions will *not* be downloadable (that would require parsing the
requested filename to try and find a version). Hey, it's better than no support at all =)