[zanata/zanata-server] b0dab9: Add documentation for the database migration

[GitHub]

  Branch: refs/heads/postgresql
  Home:   https://github.com/zanata/zanata-server
  Commit: b0dab916be4eabfce3463d76aab07690ad2ae9f1
      https://github.com/zanata/zanata-server/commit/b0dab916be4eabfce3463d76aab07690ad2ae9f1
  Author: Carlos A. Munoz <camunoz at redhat.com>
  Date:   2015-09-22 (Tue, 22 Sep 2015)

  Changed paths:
    M docs/release-notes.md
    A docs/user-guide/system-admin/configuration/postgresql.md
    M mkdocs.yml

  Log Message:
  -----------
  Add documentation for the database migration