disambiguation and tags are in local language

TOFIX:
    needs to query the api every time to know each label's name

[mod] remove the kickass engine from settings.yml

support time range search

[fix] close #637 : the search box doesn't overlap the menu.

moving a comma

[fix] Close #640 : remove MapQuest maps.

[fix] deviantart engine xpaths

Fix anomalous backslash in string

These lines were added to fix a js image load issue (#535) what i cannot reproduce.
Hopefully we don't see it again

Add Google Scholar search engine

utils/fetch_currencies: fix comment

Add ScanR structures search engine

[fix] multilingual duckduckgo

only works if both country and language are set

In theory ScanR should also search for projects but the API is different,
so we'd need another engine.