Added specs for strings with multi-byte characters
When adjusting tokens for insertions, default affinity to :right for better results when merging subtitle tokens into .at file.
Fixed bug where AbsoluteSuspendedTokens weren't adjusted correctly for insertions. The fix was to update the ref_pos when deciding whether to adjust a token for an insertion at ref_pos. 

This fixes https://github.com/imazen/repositext-vgr-specs/issues/16
Updated comments, added a few more specs