Fixed OutputScrapingExecutionFailure to handle failures with a multi-line description.
- Some tweaks to the formatting of the error message received when no tool chains are available to build a particular platform.
- Changed DefaultToolChainRegistry so that it does not create a ToolChain instance if no defaults have been registered.
A small tweak to unavailable message.
Fixed unit test for changes to DefaultToolChainRegistry.
Javadocs.
Removed debug println().