docs/: prefix manpages with "containers-"

Prefix manpages with "containers-" and propagate the change into the
manpages.  Furthermore, make sure that the manpages have the NAME and
DESCRIPTION section to make them be indexed by `man -k` and `apropos`.

Fixes: #492
Signed-off-by: Valentin Rothberg <vrothberg@suse.com>

docs/policy.json.md → docs/containers-policy.json.md

@@ -1,9 +1,9 @@
-% POLICY.JSON(5) policy.json Man Page
+% CONTAINERS-POLICY.JSON(5) policy.json Man Page
 % Miloslav Trmač
 % September 2016
 
 # NAME
-policy.json - syntax for the signature verification policy file
+containers-policy.json - syntax for the signature verification policy file
 
 ## DESCRIPTION
 
@@ -278,4 +278,6 @@ selectively allow individual transports and scopes as desired.
   atomic(1)
 
 ## HISTORY
+August 2018, Rename to containers-policy.json(5) by Valentin Rothberg <vrothberg@suse.com>
+
 September 2016, Originally compiled by Miloslav Trmač <mitr@redhat.com>

docs/registries.conf.5.md → docs/containers-registries.conf.5.md

@@ -1,14 +1,17 @@
-% registries.conf(5) System-wide registry configuration file
+% CONTAINERS-REGISTRIES.CONF(5) System-wide registry configuration file
 % Brent Baude
 % Aug 2017
 
 # NAME
-registries.conf - Syntax of System Registry Configuration File
+containers-registries.conf - Syntax of System Registry Configuration File
 
 # DESCRIPTION
-The REGISTRIES configuration file is a system-wide configuration file for container image
-registries. The file format is TOML.  The valid categories are: 'registries.search',
-'registries.insecure', and 'registries.block'.
+The CONTAINERS-REGISTRIES configuration file is a system-wide configuration
+file for container image registries. The file format is TOML. The valid
+categories are: 'registries.search', 'registries.insecure', and
+'registries.block'.
+
+By default, the configuration file is located at `/etc/containers/registries.conf`.
 
 # FORMAT
 The TOML_format is used to build a simple list format for registries under three
@@ -46,5 +49,8 @@ registries = ['registry.untrusted.com', 'registry.unsafe.com']
 ```
 
 # HISTORY
-Aug 2017, Originally compiled by Brent Baude <bbaude@redhat.com>
+Aug 2018, Renamed to containers-registries.conf(5) by Valentin Rothberg <vrothberg@suse.com>
+
 Jun 2018, Updated by Tom Sweeney <tsweeney@redhat.com>
+
+Aug 2017, Originally compiled by Brent Baude <bbaude@redhat.com>

docs/registries.d.md → docs/containers-registries.d.md

@@ -1,7 +1,11 @@
-% REGISTRIES.D(5) Registries.d Man Page
+% CONTAINERS-REGISTRIES.D(5) Registries.d Man Page
 % Miloslav Trmač
 % August 2016
-# Registries Configuration Directory
+
+# NAME
+containers-registries.d - Directory for various registries configurations
+
+# DESCRIPTION
 
 The registries configuration directory contains configuration for various registries
 (servers storing remote container images), and for content stored in them,