Postgresql doesn't accept replication connection
The database name has to be replication as all does not cover replication connections.

host    replication    postgres             127.0.0.1/0               trust


The PostgreSQL documentation further says:


  The value replication specifies that the record matches if a
  replication connection is requested (note that replication connections
  do not specify any particular database). Otherwise, this is the name
  of a specific PostgreSQL database. Multiple database names can be
  supplied by separating them with commas. A separate file containing
  database names can be specified by preceding the file name with @.