8028544: Add SourceVersion.RELEASE_10
8028546: Add -source 10 and -target 10 to javac
Reviewed-by: jjg, smarks

6415644: Make javax.lang.model.SourceVersion more informative
Reviewed-by: jjg

8136494: Update "@since 1.9" to "@since 9" to match java.version.specification
Reviewed-by: alanb, chegar, lancea

8146572: Update "@since 1.9" to "@since 9" to match java.version.specification [langtools]
Reviewed-by: darcy

8087205: Follow-up fix in langtools for JDK-8085822
Reviewed-by: darcy

8085822: JEP 223: New Version-String Scheme (initial integration)
Reviewed-by: erikj, dcubed, dholmes, alanb
Contributed-by: Kumar Srinivasan <kumar.x.srinivasan@oracle.com>, Magnus Ihse Bursie <magnus.ihse.bursie@oracle.com>

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