No need to declare the Manifest version because version 2 is the default
No reason for putting the manifest in the ${basedir}

Actually, the one single reason may be so that the sbt.full.library project can
be correctly consumed by the core project, when imported in the workspace. If
that's the reason, and you want to keep having this (the alternative is to
simply depend on the currently installed Scala IDE, and hence never import the
sbt.full.library and compiler.interface bundles, please say so.)

\cc @dragos @skyluc @huitseeker
No need to put the sbt version number in the bundle name
Adding organisation information in the POM to reduce duplication

In fact, the default value for Bundle-Vendor is ${pom.organization.name}
Added source bundle for Sbt compiler interface
Deleted unneeded import-package clauses in toolchain MANIFESTs

The maven build does no longer spits out warnings for unused package imports in MANIFESTs.