Changed SAMRecord.toString() to emit the SAM format string with all fields

[tfenne]

Description

SAMRecord has historically output an abbreviated format in toString(). I think more often than not this is confusing to users, since a SAMRecord has a well defined String format. Moreover the toString() method is used extensively by TestNG to display when two SAMRecord instances are not equal - and the vast majority of the time the toString() output did not contain the differences.

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• Extended the README / documentation, if necessary
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