Updated jline and rebuilt.

Two years of atrophy. Now using sbt 0.12.3 and latest
versions of jansi, etc.
SI-7429 Fix checkinit build failure in Contexts

The recent refactoring in Contexts resulted in an uninitialized
field access. This wasn't deadly, as it was already compensating
for this by expecting a null value for `outer` during in the body
of the constructor of Contexts when extended by NoContext.

This commit reworks that code a little to avoid dereferencing the
overriden `outer` field.

A similar mistake in `ImportContext` is also corrected.
SI-6784 Localize feature imports in scala.swing.

These were inadvertantly added to the public API in f15dc74 for anyone
importing scala.swing._, which unintentionally enabled reflectiveCalls
and implicitConversions for clients of the API.

This change breaks the source compatibiliy poilicy, rather than
deprecating these, based on the extremely low chance that someone is
using these in something like:

    import scala.swing._; println(implicitConversions)
Address a deprecation warnings in scala-swing.

While I was in the neighbourhood.
Merge pull request #2443 from paulp/pr/jline

Updated jline and rebuilt.
Merge pull request #2465 from retronym/ticket/6784

SI-6784 Localize features imports in scala.swing
Merge pull request #2463 from retronym/ticket/7429

SI-7429 Fix checkinit build failure in Contexts