[doc] Update README to propose a compatible maven

"make apps" fails with errors using maven2 package.
It works fine if we use maven3 (default maven package on Ubuntu).
HUE-2190 [search] Truncate function doesn't work anymore

Fixed triple escaping for functions
HUE-2184 [core] Connect to Oracle via Service Name
HUE-2188 [beeswax] Remove Email me on completion