* Completed property hooks, so that the underlying Ant1 project
  is not used for setting, getting or resolving properties.

* Made PropertyResolver.resolveProperties()take a TaskContext,
  instead of Avalon Context. (We can always split out a generic
  interface later, if need be.) Ant1 compatibility layer user
  ClassicPropertyResolver, which needs a better name.

* Added modified BuildException, which incudes a Myrmidon-friendly
  getCause() method, to allow Ant1 exceptions to be properly cascaded.

* DefaultTaskContext:
    - Allow "+" in property names.
    - Implemented DefaultTaskContext.getProperties()
    - No longer implements avalon Context (not needed)


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271924 13f79535-47bb-0310-9956-ffa450edef68

* Use modified version of Path.java, to provide all
  available classes in Path.systemClasspath.
  (Uses LoaderUtils.java taken from Mutant proposal,
  for obtaining complete classpath from a ClassLoader.)

* Removed <ant> and <antcall> from ant1compat.atl
  descriptor, since they don't work.

* Modified build so that xdoclet.jar and
  jdepend.jar aren't included in dist/lib.


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271907 13f79535-47bb-0310-9956-ffa450edef68

* TransformingProjectBuilder
    - Performs an XSL transform on all ".xml" build files.
    - Identity transform is used for projects with "version" attribute.
    - Added xalan.jar to lib - replaced jaxp.jar with xml-apis.jar

* Compatibility Layer
    - Described more fully in src/ant1compat/README.txt
    - Uses pre-compiled Ant1 jar files for Ant1 code-base.
      Insulates from changes in the main tree, and simplifies build.
    - "ant." prefix used for all ant1 tasks


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271884 13f79535-47bb-0310-9956-ffa450edef68