[FIX] Multiline texts could not be matched for tranlations
[FIX] OPW 590091 : not searchable functional fields aren't removed from advanced search
[FIX] typo & imp
[FIX] handling of multiline strings during qweb translation

Javascript regexps don't provide a DOTALL flag (to make `.` match
newlines) so have to replace `.` by `[\s\S]` hack, as *that* will
match newlines as well as all other characters.

Note: the `m` flag has a different meaning, it makes `^` and `$` match
      the start and end of lines rather than the start and end of the
      string itself.
[IMP] replace literal values by symbolic ones for node types dispatching
[FIX] exclude non-searchable function fields from the advanced search's list