rework directory display functions

`smc_get_dir_office_manager()` and `smc_dir_listing()` now both use
the new `smc_get_dir_bio()` to generate markup.
only show office mgrs once in dir listing, closes #31
use mailto: and tel: on directory bios, closes #64
Merge branch 'master' of https://github.com/templesmc/smc-themes