manual-text: make sure URLs are displayed if a link text was provided

When the asciidoc source contain URLs of the form:
    http://example.com[An example website]
the text representation of the manual would only contain:
    An example website
without displaying the actual URL.

This patch adds an asciidoc configuration file that sets the inline macros
for several URL types so that the display becomes:
    An example website [http://example.com]
For URLs where no link text was provided, the display becomes:
    http://example.com
which is the same as before.

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire@gmail.com>
Acked-by: Samuel Martin <s.martin49@gmail.com>
Reviewed-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Tested-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

docs/manual/asciidoc-text.conf

@@ -0,0 +1,17 @@
+# Refer to following asciidoc documentation:
+#     http://www.methods.co.nz/asciidoc/userguide.html
+# In particular sections "Macros" and "Attribute References"
+#
+# For hyperlinks, show 'link text [URL]' (if link text provided) or 'URL'
+[http-inlinemacro]
+{0=}{0? [}{name}:{target}{0?]}
+[https-inlinemacro]
+{0=}{0? [}{name}:{target}{0?]}
+[ftp-inlinemacro]
+{0=}{0? [}{name}:{target}{0?]}
+[file-inlinemacro]
+{0=}{0? [}{name}:{target}{0?]}
+[irc-inlinemacro]
+{0=}{0? [}{name}:{target}{0?]}
+[mailto-inlinemacro]
+{0=}{0? [}{name}:{target}{0?]}