restore .vm usage lost in .xdoc to .md migration

[hboutemy]

this fixes Reproducible Builds issue detected in recent releases: https://github.com/jvm-repo-rebuild/reproducible-central/blob/master/content/org/mybatis/mybatis-spring/mybatis-spring-3.0.0.diffoscope

as you can see:

• user directory is currently stored in .jar file
• site content is stored in -sources.jar in user directory

this was caused by the migration from .xdoc to .md in 322a051 where the .xdoc.vm was changed to .md with a tweak on resources filtering because of a "classical" conflict on ##between Velocity and Markdown https://maven.apache.org/plugins/maven-site-plugin/examples/creating-content.html#common-issues-and-workarounds

[coveralls]

Coverage remained the same at 89.456% when pulling 1ce16d0 on hboutemy:velocity-markdown into 9b1f5a1 on mybatis:master.

[kazuki43zoo]

@hboutemy Thanks you for your reporting!!

I found a solution for fixing this problem, it is maven.source.excludeResources=true as maven properties.
I prefer to use .md file instead of .vm file cannot render on GitHub UI.

[hboutemy]

I prefer to use .md file instead of .vm file cannot render on GitHub UI.

I see, thanks for sharing

it is maven.source.excludeResources=true as maven properties

this one means you will not copy the .md resources but also not any other: your are abusing the main resources definition in pom.xml.

I think the best way would be to configure an execution of resource:copy-resources with your specific resources: https://maven.apache.org/plugins/maven-resources-plugin/usage.html

[hboutemy]

@kazuki43zoo I proposed #763 PR as an implementation of the use of maven-resources-plugin that I proposed