8163517: Various cleanup in java.io code
Reviewed-by: shade, rriggs, redestad

8130679: Writer/StringWriter.write methods do not specify index out bounds
Summary: Add throws tag indicating IndexOutOfBoundsExcepion to write() methods which have an index parameter.
Reviewed-by: chegar, prappo, rriggs

8132468: docs: replace <tt> tags (obsolete in html5) for java.io, java.lang, java.math
Reviewed-by: lancea, dfuchs, smarks

8068498: Remove constructor dependency on line.separator from PrintWriter and BufferedWriter
Reviewed-by: alanb, sherman

8054834: Modular Source Code
Reviewed-by: alanb, chegar, ihse, mduigou
Contributed-by: alan.bateman@oracle.com, alex.buckley@oracle.com, chris.hegarty@oracle.com, erik.joelsson@oracle.com, jonathan.gibbons@oracle.com, karen.kinnear@oracle.com, magnus.ihse.bursie@oracle.com, mandy.chung@oracle.com, mark.reinhold@oracle.com, paul.sandoz@oracle.com