relax SVN archive

Created version.version_full() from the code in generic_fns.exp_info.

The get_revision() and get_url() functions have had the 'get_' part removed.

Fixes for the software add() method.

Non-list data can now be used by TagTable.create_tag_table().

The method converts to lists on the fly.

TagTable.create_tag_table() now handles single element data.

This allows the single element data to be submitted simultaneously with list data.

Created the bmrb_write_software() function for dumping the software info into the BMRB file.

All attributes (even those of None) are being stored.

Import fix from the previous module deletion.

Removed the kludgy bmrb_saveframes module and shifted the code into exp_info.

Shifted the software() and software_select() functions into their own module, 'generic_fns.exp_info'.

Created the bmrb.software() user function for manually specifying the software used.