Major Improvements:

* Move to 2.9.1 for project definitions and plugins
* Drop support for 2.7
* Settings overhaul, mainly to make API documentation more usable
* Support using native libraries in `run` and `test` (but not `console`, for example)
* Automatic plugin cross-versioning.  Use

	    addSbtPlugin("group" % "name" % "version")

    in `project/plugins.sbt` instead of `libraryDependencies += ...`   See [Plugins](https://github.com/harrah/xsbt/wiki/Plugins) for details


Fixes and Improvements:

 * Display all undefined settings at once, instead of only the first one
 * Deprecate separate `classpathFilter`, `defaultExcludes`, and `sourceFilter` keys in favor of `includeFilter` and `excludeFilter` explicitly scoped by `unmanagedSources`, `unmanagedResources`, or `unmanagedJars` as appropriate (Indrajit)
 * Default to using shared boot directory in `~/.sbt/boot/`
 * Can put contents of `project/plugins/` directly in `project/` instead.  Will likely deprecate `plugins/` directory
 * Key display is context sensitive.  For example, in a single project, the build and project axes will not be displayed
 * [#114](https://github.com/harrah/xsbt/issues/114), [#118](https://github.com/harrah/xsbt/issues/118), [#121](https://github.com/harrah/xsbt/issues/121), [#132](https://github.com/harrah/xsbt/issues/132), [#135](https://github.com/harrah/xsbt/issues/135), [#157](https://github.com/harrah/xsbt/issues/157): Various settings and error message improvements
 * [#115](https://github.com/harrah/xsbt/issues/115): Support configuring checksums separately for `publish` and `update`
 * [#118](https://github.com/harrah/xsbt/issues/118): Add `about` command
 * [#118](https://github.com/harrah/xsbt/issues/118), [#131](https://github.com/harrah/xsbt/issues/131): Improve `last` command.  Aggregate `last <task>` and display all recent output for `last`
 * [#120](https://github.com/harrah/xsbt/issues/120): Support read-only external file projects (Fred)
 * [#128](https://github.com/harrah/xsbt/issues/128): Add `skip` setting to override recompilation change detection
 * [#139](https://github.com/harrah/xsbt/issues/139): Improvements to pom generation (Indrajit)
 * [#140](https://github.com/harrah/xsbt/issues/140), [#145](https://github.com/harrah/xsbt/issues/145): Add standard manifest attributes to binary and source jars (Indrajit)
 * Allow sources used for `doc` generation to be different from sources for `compile`
 * [#156](https://github.com/harrah/xsbt/issues/156): Made `package` an alias for `package-bin`
 * [#162](https://github.com/harrah/xsbt/issues/162): handling of optional dependencies in pom generation
