Fix #180. Filter properly user rules in RESTServiceImpl

[offtherailz]

Actually Access rules from ResourceDAOImpl.findUserSecurityRule returns all rules available instead of returning rules that match user and .
RESTServiceImpl expects only to find only one result (that is not properly correct because there is not any check about unique rules for same user/resource), so it gets the first rule available and checks this rule to find out read or write access information. But because of the bug above, any rule found on the db before the user's one is valid. So it returns true anyway.

I changed this behavior to check all rules returned by the ResourceDAOImpl and ignore the ones not referred to the user.

NOTE: I implemented a fix that ignores not valid rules in RESTServiceImpl because this part is testable ( test ResourceDAOImpl is hard instead) and because ResourceDAOImpl.findUserSecurityRule is deprecated, so it's not too useful maintain it.

[coveralls]

Coverage increased (+0.7%) to 32.712% when pulling 99a7c4c on offtherailz:fix_#180 into d4b6dff on geosolutions-it:master.