dev-db/sqldeveloper: Use jtds:1.3, auto select 1.8 JVM, other fixes

dev-db/sqldeveloper: Use jtds:1.3, auto select 1.8 JVM, other fixes

Java team needs to remove Java 6 ASAP and jtds:1.2 is holding this
back. Upstream suggests 1.2 but 1.3 is reported to work. I wasn't able
to test against a real database but it did at least try to connect.

Asking users to manually switch their JVM before using this isn't very
polite and not usually necessary thanks to Gentoo's launcher
scripts. Those scripts cannot feasibly be used here but we can at
least write package.env and use gjl to select the JVM intelligently.

Other fixes:

 * Remove java-config from RDEPEND, it's implied by java-pkg-2 eclass.
 * Add some missing dies and remove some unnecessary dies.
 * Use newicon instead of mv + doicon.
 * Use exec in launcher to prevent lingering process.

Package-Manager: portage-2.2.27