to be used in <if>. Tests updated for new functionality.

* Ant1 conversion stylesheet uses nested <is-set> condition on <if>,
  to replicate Ant1 behaviour of 'if=' and 'unless=' on targets.

* ant1compat antlib generated as part of standard build.

* Minor build cleanup: ${custom-tasks-dir} -> ${build.custom-tasks} for
  consistency.

* Ant1CompatProject now uses ProjectHelper for property resolution, rather than
  trying to duplicate Ant1 behaviour.

* Added tests for Ant1 Compatibility layer. These have been exclude from regular
  build, as they fail when run under Ant1.4.1, because the JUnit task *always*
  places ant.jar *first* in the JUnit classpath. Tests work under Ant1.5alpha,
  since it adds ant.jar *last* by default. (Tests also function correctly by
  invoking JUnit directly - or with Intellij JUnit integration).


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@272101 13f79535-47bb-0310-9956-ffa450edef68

in the current project, or any referenced project.
* <ant1.ant> now works by executing AntTask.
* Fixed minor bug in DefaultClassloaderManager which was causing NPEs
  in URLClassLoader.
* DefaultTaskContext now removes properties when they are set to null.
  (rather than throwing a NPE inside HashMap).


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@272067 13f79535-47bb-0310-9956-ffa450edef68

* 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