* Use define-command to define and register a command
* Introduce the notion of workspace to store intermediate and target files.
* Update Makefiles for new intended output paths

  and other types of related errors.
+ Changed all externals to be :asdf instead of :build.
+ tweak dependencies

in HANDLE-TARGET. Replaced by better checking in CANONICALIZE-FULLNAME.
Changed ENSURE-VALID-FULLNAME to take the keywords of 'type' and
'original-name' which help print out a good error message.
Changed 'xcvb ssr' to output symbols in lowercase.

Check that the build name specified to list-files is absolute.

Update documentation.
Fix implicit build (default without --build).

output without a baktrace.

* extract fasl type from target:
 at least lispworks depends on pathname type and its fasl type varies!
* rucksack not available on clisp (and needed fixes; see our xcvb repo of it)
* accept compile-file failure semantics of clisp
* suppress duplicate entries for a directory in the source-registry:
 The first one wins, with its recurse and exclude flags.
* fix hello and test/runme
* fix various option parsing mistakes

Also, now that we're importing symbols from ASDF,
avoid redefining them due to a conflict. Oops.

Usually we don't need a backtrace when the user simply did the wrong
thing.

Extract version from git when finalizing the image (requires cl-launch 3.009).
On CCL/windows, work around bug ccl bug 858 in run-program.
Simplify some tests for run-program, fix others.

Extract version from git when finalizing the image (requires cl-launch 3.009).
On CCL/windows, work around bug ccl bug 858 in run-program.
Simplify some tests for run-program, fix others.

validating the CL_SOURCE_REGISTRY envvar.

CL_SOURCE_REGISTRY environment variable. XCVB will now:

CL_SOURCE_REGISTRY=
  Recurse to inherited configuration.

CL_SOURCE_REGISTRY=/valid/path/to/systems
  Find all toplevel systems at the path stated.

CL_SOURCE_REGISTRY=/valid/path/to/systems//
  Find all systems at the path stated and recurse subdirectories

CL_SOURCE_REGISTRY=/invalid/path/or/no/systems/present
  No systems will be found and the source registry is considered empty.

CL_SOURCE_REGISTRY=../somewhere/else
  Any relative paths will be flagged as an error and XCVB will stop executing.

when emitting output so it looks nice on the screen.
Added much more instrumentation of what xcvb isdoing at verbosity 10.
Got rid of some commented out code we don't need.

Rename search-path to source-registry, registry to grain-registry.
Extract ASDF implementation identifier from target, so we may use it later.

added pathname to some grain-related error messages
added to TODO list

Unrot release and test scripts.
Tested: XCCL=stccl make test LISP=ccl

Also, fix ssr with require supersession and fix xcvb-farmer conditionals.

Also, supersede some sbcl contrib asdf systems with appropriate requires.

TODO for ECL: distinguish linkable object files from loadable shared objects.

Passes pre-release-test.

Give proper semantics to resolve-absolute-module-name and resolve-module-name.
Make the hello example work properly.
hello now uses the generate functionality to extract version from parent XCVB.
Have log-format do fresh-lines for you.
Make sure builds are only interned once.
Recognize that builds may be invalid because of inherited conflict.

Easy functionality: version, ssr and a2x work.