Replace eval() with call()
Change docount to use call()

Avoid shell-like quoting nonsense whenever possible
Fix typos
Decompose sexp#move_to_adjacent_element
Implement prev_bracket and next_bracket

Overrides the ( and ) mappings, which are not particularly useful for
editing lisp
Change adjacent element motion mappings
Rename g:sexp_wrap_insert -> g:sexp_insert_after_wrap
Implement end-of-element movement