Translate 'Tatoeba' and uniformize title.

<pagename> - <sitename> is most commonly used and it allows to
know what page the tab/window contains by just looking at the
first characters.

Languages that don’t commonly use Latin characters should be able
to express the site name appropriately in the title. We won’t
loose the English keyword “tatoeba” since it is in the URL already.
Fix broken titles.

Add page title where it was missing,
or append the site name where it was missing.
Enhance the latest contributions page.

Display differently contributions that are not the latest one for a given
sentence, so that these can be easily ignored when glancing at the latest
contributions.
Merge branch 'master' into titles

Conflicts:
	app/views/sentences_lists/index.ctp
#480 Rephrase sql fields to proper English
#480 Revert according to previous comments, without underscores
Fixed previous commit
Add a button to link sentences by id
'git pull' before pushing to prevent merge
Use a helper function to format page titles.
Fix #447 while we’re at it.
Simplified rendering using a separate template.
Optimize and fix the Sphinx indexes SQL query.

By taking advantage of cross-linking, we can get both direct and indirect
translations using a single query. We start by querying indirects ones,
and if an indirect one equals the original one, it means we got back to
the starting point, and in this case we keep the direct translation instead.

The only downside of this approach is that it doesn’t work when two
sentences aren’t cross-linked. There are currenly only five such broken
links on the production server, visible by running the follwing query:

select s.sentence_id, s.translation_id
from sentences_translations as s
left join sentences_translations s2
on s.translation_id = s2.sentence_id
and s.sentence_id = s2.translation_id
where s2.sentence_id is NULL;

Some quick comparison of the data returned by this new query shows that
it’s is more accurate. The previous one happened to return the original
sentence language as a translation language from time to time, whereas this
query doesn’t. This problem was visible when running a search with the same
source language as the target one, and a keyword of that language.

  http://tatoeba.org/sentences/search?query=fish&from=eng&to=eng

Such a query returned many English sentences without any translation,
whereas it should only return English sentences translated into English.
So this commit fixes that too.

Some benchmarks.

Running the query to generate indexes for Turkish sentences (about 200k)
on the production server. That’s about 60% faster and uses less memory.

           before      after

          0:54.25    0:33.74
time to   0:54.85    0:40.27
run the   0:59.39    0:33.71
query     0:56.75    0:31.87
          0:54.51    0:35.62

Maximum
resident   213 ko     182 ko
set size
Logs visual rework

I didn't feel very comfortable having obsolete logs displayed with a stroke text. It gave the impression that the sentence was deleted.
I couldn't find a satisfying way to express that a log entry was obsolete based on the previous design so I sort of redesigned the whole thing.
Merge pull request #485 from Ppjet6/update_translations

'git pull' before pushing to prevent merge
Obsoletize latest contributions on homepage.
Translations updated via update-translations.sh.
Merge branch 'sql_to_english' of https://github.com/Ppjet6/tatoeba2
Some more visual changes for logs.

- Moved the date to the left side.
- Pastelized colors.
- Changed the padding and margins for clearer separations between
entries.
Members currently contributing in latest contributions annexe.