app_macro: Remove deprecated module.

For most modules that interacted with app_macro, this change is limited
to no longer looking for the current context from the macrocontext when
set.  Additionally, the following modules are impacted:

app_dial - no longer supports M^ connected/redirecting macro
app_minivm - samples written using macro will no longer work.
The sample needs a re-write

app_queue - can no longer a macro on the called party's channel.
Use gosub which is currently supported

ccss - no callback macro, gosub only

app_voicemail - no macro support

channel  - remove macrocontext and priority, no connected line or
redirection macro options
options - stdexten is deprecated to gosub as the default and only
pbx - removed macrolock
pbx_dundi - no longer look for macro

snmp - removed macro context, exten, and priority

ASTERISK-30304

Change-Id: I830daab293117179b8d61bd4df0d971a1b3d07f6

configs/samples/users.conf.sample

@@ -22,7 +22,7 @@ fullname = New User
 ;
 userbase = 6000
 ;
-; Create voicemail mailbox and use use macro-stdexten
+; Create voicemail mailbox
 ;
 hasvoicemail = yes
 ;