Contining task 172

Add column   fk_c_element_role	into llx_actioncomm_ressource to manage
role of linked element
As exemple we can have 
fk_element = 1
element_type= "user" or contact or place or whatever element
fk_c_element_role = 1 // 'Guest' or Host or whatever define in
dictionnary
fk_c_element_status = Present // or whatever define in dictionnary
according element type