Add new symbol: !mavenArtifact

[CyrilDeverson]

This symbol enables user to define dependencies available from a remote maven repository.
To option is particularly interesting when no pom file is available locallly on the FitNesse server.

Additionally, this enhancement uses an external maven installation (not the embedded one) which make it easier to configure and update.

[amolenaar]

Looks good. Just uncertain about the temp file generation for the to-be fetched artefact.

[amolenaar]

Isn't there a way to obtain a resolver and get the dependency directly? Creating a temp file does not look like the right solution for this.

[CyrilDeverson]

I tried to do so at a first stage (tried to call dependency:get and then dependency:build-classpath). But I didn't find any good way that would not lead me to re-code some internal features of maven so I preferred use mvn just as a normal client would and create a temporary pom file (which is the normal way as a maven point of view).
Please also consider that using the !pomFile symbol you need to put a specific pom file local to the fitnesse server with no way to download it automatically from maven and that is what I wanted to simplify with this new symbol: just define the group/artifact/version your fixture depends on and fitnesse will do the job by delegating dependency resolution to maven.
Could you explain the reason why a temp file doesn't look like the right solution?