Document importing ZionWorx songs

[Samuel Findlay]

The ZionWorx (CSV) importer in the song import wizard instructs the user:
"First convert your ZionWorx database to a CSV text file, as explained in the User Manual.", where <User Manual> is a link to this URL [1].

General info about the ZionWorx importer (including which fields it imports) is contained in the ZionWorxImport class docstring [2]. Information about using TdbDataX is also in the wiki [3].

The user must take these steps to convert their ZionWorx database into a CSV file:
1. Download tdbdatax "TurboDB Data Exchange" from dataWeb [4].
   * Windows: tdbdataX.zip
   * Linux: tdbdatax.tar.gz
   * Mac: find a Windows/Linux computer (NB ZionWorx is a windows-only application)
2. Extract the single executable and copy it into the ZionWorx database directory (which contains MainTable.dat)
   * default on Win 7/Vista: C:\ProgramData\ZionWorx\2.6\Data
   * default on Win XP: C:\Documents and Settings\All Users\ZionWorx\2.6\Data
3. Open a command-line/shell in the ZionWorz database directory, and run this command:
   $ tdbdatax MainTable.dat songstable.csv -fsdf -s, -qd

[1] http://manual.openlp.org/songs.html#importing-from-zionworx
[2] http://bazaar.launchpad.net/~openlp-core/openlp/trunk/view/head:/openlp/plugins/songs/lib/zionworximport.py
[3] http://wiki.openlp.org/Development:ZionWorx_-_Song_Data_Format
[4] http://www.dataweb.de/en/support/downloads.html