abcl-asdf maybe-parse-mvn ignores version information

[Cyrusharmon]

If one tries to add an :mvn component to an ASDF system, the version info is always ignored and "LATEST" is used.

e.g. in an example like this
....

:components
((:mvn "junit/junit" :version "3.8.2")

....

the version info is ignored.

[Cyrusharmon]

Patch that fixes maybe-parse-mvn to respect version information

[Mark Evenson]

Slyrus has released the code associated with this bug [on github][1].

[1]: ​git://github.com/slyrus/abcl-cdk.git

[Mark Evenson]

(In [13900]) abcl-asdf: Clarify the version setting code for MVN compoments.

Fix #204, but considerably beyond the patch the Cyrus Harmon submitted.

Drastically simplified the ASDF:MAYBE-PARSE-MVN function to take
advantage of the fact that we are in the ASDF namespace. At least the
function now makes sense

Parts of ASDF *reallY* want ASDF:VERSION to be a triple of intergers,
and never anything more, which is part of the reason for the
shennigans here.

[Mark Evenson]

(In [13901]) Part of Fix #204: require the use of maven-3.0.4.

Slyrus reports that some parts don't work with maven-3.0.3, so as a
favor to user bump requirement.

Underneath: Aether is a mess, but looks like it is getting better.