Updates to the new sbinary and sbt builds

Uses the updated build command for sbinary and sbt.
Uses '-predenting' suffix for sbinary.
No more use Eclipse to generate the update-site for refactoring.
No more use Eclipse to generate the update-site for toolchain.
Fixes merging problem when not building the IDE.
Adds support to provide a different Scala IDE repo.
Add support to specify a worksheet repo
Updates needed to build 4.0.0-b01

Adds support to specify a SBT version name (to be used in build toolchain and scala-ide).
Adds support to specify a version tag for the worksheet build.
Updates the worksheet eclipse profiles to the new name (from plugin-profiles).
Updates the scala profiles used for the worksheet build (from plugin-profiles).
Adds info about the 2.11.x ecosystem.
Updated commands used to release the latest IDE.