Changes to answered state filtering of proposals

It should be possible to configure the default filtering option regarding the answered state of the proposals. Currently the system is showing only accepted proposals by default. This was a direct feedback from the citizens that said that it is outrageous that their idea has been removed because some city official didn't like it. The idea is still in the system but it is just hidden by this filter and therefore the user did not find it. It should be also possible to see the rejected ideas when the answering is disabled. Currently the answering option is no longer needed because all ideas have been already answered and the process has proceeded to the voting stage. However, the people that do not see their idea still want to see the reason why their idea didn't proceed to voting but they are unable to find it. Therefore two changes should be implemented: - Allow configuring the default answer filter for the proposals component - Allow filtering by the answer state after answering is disabled