[user-guide] Fix markup for easier translation

In the previous version, the string contains a backslash after
a closing ** markup. It is rendered in English version, but
it cannot be rendered properly even if we try to use a similar
markup in translations. (The only way I found to make Japanese
translation rendered properly is to use the proposed way.)

The proposed string changes nothing in English version
and make translators easy to handle the string.
There seems no meaning in using a backslash here.

Change-Id: If1ad1aedb235e216c66ab0a4f8307b873c69f1e4

doc/user-guide/source/backup_db_incremental.rst

@@ -13,7 +13,7 @@ handles the complexities of applying the chain of incremental backups.
 This example shows you how to use incremental backups with a MySQL
 database.
 
-**Assumptions. **\ Assume that you have created a regular
+**Assumptions.** Assume that you have created a regular
 backup for the following database instance:
 
 -  Instance name: ``guest1``

doc/user-guide/source/create_db.rst

@@ -62,7 +62,7 @@ Create and access a database
       administrative user must create a custom flavor by using the nova
       ``flavor-create`` command.
 
-   **MySQL example. **\ This example creates a flavor that you can use
+   **MySQL example.** This example creates a flavor that you can use
    with a MySQL database. This example has the following attributes:
 
    -  Flavor name: ``mysql_minimum``

doc/user-guide/source/dashboard_databases.rst

@@ -12,7 +12,7 @@ handling complex administrative tasks.
 Create a database instance
 ~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-**Prerequisites. **\ Before you create a database instance, you need to
+**Prerequisites.** Before you create a database instance, you need to
 configure a default datastore and make sure you have an appropriate
 flavor for the type of database instance you want.
 
@@ -53,7 +53,7 @@ flavor for the type of database instance you want.
    Make sure an appropriate flavor exists for the type of
    database instance you want.
 
-**Create database instance. **\ Once you have configured a default
+**Create database instance.** Once you have configured a default
 datastore and verified that you have an appropriate flavor, you can
 create a database instance.
 

doc/user-guide/source/manage_db_config.rst

@@ -202,7 +202,7 @@ Bulk-configure a database or databases
    As you can see, the ``sync_binlog`` option is now set to ``1``, as
    specified in the ``group1`` configuration group.
 
-**Conclusion. **\ Using a configuration group to set a single option on
+**Conclusion.** Using a configuration group to set a single option on
 a single database is obviously a trivial example. However, configuration
 groups can provide major efficiencies when you consider that:
 
@@ -214,7 +214,7 @@ groups can provide major efficiencies when you consider that:
 Used in this way, configuration groups let you modify your database
 cloud configuration, on the fly, on a massive scale.
 
-**Maintenance. **\ There are also a number of useful maintenance
+**Maintenance.** There are also a number of useful maintenance
 features for working with configuration groups. You can:
 
 -  Disassociate a configuration group from a database instance, using

doc/user-guide/source/set_up_clustering.rst

@@ -21,7 +21,7 @@ Each cluster includes:
 
 This example shows you how to set up a MongoDB sharded cluster.
 
-.. note:: **Before you begin. **\ Make sure that:
+.. note:: **Before you begin.** Make sure that:
 
    -  The administrative user has registered a MongoDB datastore type and
       version.
@@ -93,7 +93,7 @@ Set up clustering
        +-------------------+--------------------------------------+
 
 
-   .. note:: **Your application connects to this IP address. **\ The trove
+   .. note:: **Your application connects to this IP address.** The trove
       ``cluster-show`` command displays the IP address of the query router.
       This is the IP address your application uses to retrieve data from
       the database.
@@ -114,19 +114,19 @@ Set up clustering
        | b37634fb-e33c-4846-8fe8-cf2b2c95e731 | cluster1-rs1-3 | 7         |    2 |
        +--------------------------------------+----------------+-----------+------+
 
-   **Naming conventions for replication sets and instances. **\ Note
+   **Naming conventions for replication sets and instances.** Note
    that the ``Name`` column displays an instance name that includes the
    replication set name. The replication set names and instance names
    are automatically generated, following these rules:
 
-   -  **Replication set name. **\ This name consists of the cluster
+   -  **Replication set name.** This name consists of the cluster
       name, followed by the string -rs\ *n*, where *n* is 1 for
       the first replication set you create, 2 for the second replication
       set, and so on. In this example, the cluster name is ``cluster1``,
       and there is only one replication set, so the replication set name
       is ``cluster1-rs1``.
 
-   -  **Instance name. **\ This name consists of the replication set
+   -  **Instance name.** This name consists of the replication set
       name followed by the string -*n*, where *n* is 1 for the
       first instance in a replication set, 2 for the second
       instance, and so on. In this example, the instance names are