associability of single_view (and associability preservation of some algorithms)

[jhcarl0814]

if input of these algorithms models AssociativeSequence, then output will model AssociativeSequence, because:

erase and erase_key use: iterator_range, joint_view
pop_back and pop_front use: iterator_range

iterator_range and joint_view preserve associability

if input of these algorithms models AssociativeSequence, then output will not model AssociativeSequence, because:

push_back and push_front use: single_view, joint_view
insert and insert_range use: iterator_range, single_view, joint_view

single_view does not model AssociativeSequence

can fusion let single_view model AssociativeSequence?