[bbDev] Renaming

[Michael D Adams]

In order to better facilitate WP+bb, I've renamed a bunch of  
functions and globals.  This will *really* annoy people who've got  
custom template, plugins or hacks.

Here's a list of (I think ) everything:

get_header() : bb_get_header()
get_footer() : bb_get_footer()
post_time() : bb_post_time()
get_post_time() : bb_get_post_time()
current_user_can() : bb_current_user_can()
$table_prefix : $bb_table_prefix **********  crucial one ***********
update_usermeta() : bb_update_usermeta()
map_meta_cap() : bb_map_meta_cap()
get_post() : bb_get_post();
$post_cache : $bb_post_cache
remove_action : bb_remove_action
update_user_meta : bb_update_usermeta
update_topic_meta: bb_update_topicmeta
DB_NAME : BBDB_NAME
BB_USER : BBDB_USER
BB_PASSWORD : BBDB_PASSWORD
DB_HOST : BBDB_HOST
unregister_GLOBALS() : bb_unregister_GLOBALS()
$post : $bb_post
$current_user : $bb_current_user


$post : $bb_post is the only one I wasn't sure should switch.  We can  
change it back if people don't think it will conflict.  Thoughts?

Also, some bad regex of mine may have introduced a couple typos re:  
bb_current_user_can().  I think I fixed them all in http:// 
bbpress.automattic.com/changeset/255 , though.

Michael