Better behaviour with simplified API in case of writing mp3 files

From https://java.net/jira/browse/JAUDIOTAGGER-246

Currently, when the simplified API is used for editing mp3 files, it can happen that the id3 tag of the file is of an version that does not allow the change that would need to be done. For example, a composer field might not be added to an id3v1 tag. When the simplified API is used, Jaudiotagger should detect such a situation and do one of the following:

write an id3v2 tag additionally to the id3v1 tag

write an id3v2 tag additionally to the id3v1 tag and update the id3v1 tag (for
later supported fields only)

write an id3v2 tag and delete the id3v1 tag

In each case, the content of the id3v1 tag should be copied to the id3v2 tag, except if a change to this content was explicitely requested (example: correcting typo in artist name while adding composer and lyrics of the song).

When only the following fields are altered, ISO8859-1 encoding is sufficient and strings do not exceed maximum length id3v1 tag could still be written as usual:

Artist (max. 30 characters)
Album (max. 30 characters)
Title (max. 30 characters)
Genre (1 byte)
Year (max. 4 characters)
Comment (id3v1.0 max. 30 characters, id3v1.1 max. 28 characters)

Track number (id3v1.1 only! id3v1.0 does not support track number. 1 byte)

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