allow to use multiple upload and report targets with the same name

In this feature target option must allways point to section name instead
of type. Type will be read from type option. In case if type option is
not presented it will try to check if section with architecture exists
(e.g. target = email, section = email:x86_64); if it does, the correct
section name and type will be used. Otherwise it will check if the
specified section exists; if it does, seection name and type will be
returned.

tests/testresources/core/ahriman.ini

@@ -55,13 +55,16 @@ target =
 command = rsync --archive --verbose --compress --partial --delete
 remote =
 
-[s3]
+[disabled]
+
+[customs3]
+type = s3
 access_key =
 bucket = bucket
 region = eu-central-1
 secret_key =
 
-[github]
+[github:x86_64]
 owner = arcan1s
 password =
 repository = ahriman