Added support for ODT export.

I added support for ODT export. Not all things that work in CSS work in ODT too.
Checkout this test content and you will see the difference when you compare the XHTML rendering against the ODT document:

    <typo fc:red; bg:lightyellow; fs:150%; ff:san-serif;>extended text formatting</typo>

    <typo fc:Turquoise;>Specific color text</typo>

    <typo ff:'Comic Sans MS';>Different font used</typo>

    <typo fs:200%;>Large size text</typo>

    <typo fw:900;>Heavy text</typo>

    <typo fv:small-caps;>Variant Small-Caps</typo>

    Test Test Test \\
    <typo lh:400%;>Line-Height 400% (so we have a great distance to the previos line)</typo>Hello \\
    Test Test Test \\
    Test Test Test \\

    <typo ls:20pt;>Letter spacing 50</typo>

    <typo ff:monospace;>Font family monospace</typo>

    <typo ws:50pt;>This is 50pt word space</typo>

    <typo sp:pre;>This is pre        white space</typo>

    <typo va:super;>Vertical align super</typo>Back to normal

    <typo va:sub;>Vertical align sub</typo>Back to normal

If you like the code anyway, please merge it to the master branch. If the code is merged I will write some more detailed documentation on the plugin page regarding the supported ODT export (what works, what not).

Greetings, Lars (DokuWiki-User LarsDW223)