Support semantic markup for DocBook inline elements used in Fedora docs

[fbolton]

Currently, DocBookRx supports semantic markup by applying a role to backticks, for example:

[guibutton]``Press Me``

However, it would be more elegant to use the following syntax:

[guibutton]#Press Me#

Which converts to the following HTML:

<span class="guibutton">Press Me</span>

In particular, Fedora requires support for the following tags:
Docs tagging ideas for semantic markup
https://fedoraproject.org/wiki/Docs_Tag_Discussion
Please try to keep these tags beyond what asciidoc handles natively:
acronym
application
citetitle
command
filename
guibutton
literal
option
package
parameter
replaceable
systemitem
computeroutput
example
procedure
productname
productnumber
programlisting
remark
revhistory
revision
screen