Using compiled resource on impact merge tools.

Regarding this issue: https://github.com/AIFDR/inasafe/issues/832 I changed the use of direct resources to the compiled ones.

It is working and the tests on safe_qgis are passing. The only problem remains: After some experiments by deleting the resources folder, the table on the merged impact report does not formatted correctly related to the map_qrc_to_file function (https://github.com/AIFDR/inasafe/blob/develop/safe_qgis/utilities/utilities.py#L744). Basically the same underlying problem of the unformatted panel on the dock (https://github.com/AIFDR/inasafe/issues/831)

I will work on that issue on another PR