configure-element-2.tcl

- use $$ quoting in postgres SQL
- use name parameter for SQL functions
- provide compatility with pg9
- replace deprecated "acs_sc_call" by "acs_sc::invoke"
- replace deprecated "ad_maybe_redirect_for_registration" by "auth::require_login"
- brace expressions
- favor tcl-compilable string comparisons
- don't use numeric comparison operator for non-numeric arguments
- use numeric comparison operator for truth value comparisons
- use "in" or "ni" expression instead of "lsearch"
- bump version number to indicate compatibility with 5.8.1