Move iobackends and search wrapper to common

Signed-off-by: José Luis Di Biase <josx@interorganic.com.ar>
Adding new backends file wth backends conf

Signed-off-by: José Luis Di Biase <josx@interorganic.com.ar>
Merge pull request #206 from inaes-tic/iobackends2common_review

Iobackends2common review