Document the makeJar() method

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
When writing temporary projects, use more appropriate artifactIds

When we write a temporary project, it makes more sense to use the class'
name as artifactId than a semi-random directory name of the temporary
directory we just created.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Write out pom.xml files when generating temporary projects

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Always write temporary projects for non-Maven sources

When compiling a .java file that is contained in, say, a Downloads/
directory, we definitely do not want to compile all of the .java files
available in the complete Downloads/** directory structure.

Now, we could special-case .java files containing the source for a class
in the default package, while still trying to discover .java files
recursively when the class is in a package and the directory structure
agrees with the package name.

But that would just violate the Law of the Least Surprise and confuse
people. So let's just make a temporary project in *every* case where we
do not find a pom.xml file in the expected location.

Incidentally, this makes sure that we always include pom.xml files in
the generated .jar files.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Add a unit test for makeJar()

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
TEMPORARY bump to SNAPSHOT version of MiniMaven

Required for the bug fix regarding .jar file generation with sources.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Ensure that .jar files include the correct sources

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>