Add documentation on building/running

[mycroes]

I'm trying to setup a repository with some groovy helper scripts and as such ended up here. While I tried piecing together stuff from different places I couldn't really get anything working (and neither could I get very useful error messages), so I decided to just clone this repo and see if I could get it working.

First off I ran into issues where gradle couldn't resolve all packages, so I added a repositories section. However, running gradlew check I end up with errors I'm not able to resolve:

com.mkobit.libraryexample.ExampleSrcSpockSpec > say hello to name FAILED
    java.lang.ExceptionInInitializerError at ExampleSrcSpockSpec.groovy:21
        Caused by: java.lang.reflect.InaccessibleObjectException at ExampleSrcSpockSpec.groovy:21

com.mkobit.libraryexample.ExampleSrcSpockSpec > calling a @NonCPS method FAILED
    java.lang.NoClassDefFoundError at ExampleSrcSpockSpec.groovy:21
        Caused by: java.lang.ExceptionInInitializerError at ExampleSrcSpockSpec.groovy:21

com.mkobit.libraryexample.ExampleSrcSpockSpec > using 'lock' step from plugin FAILED
    java.lang.NoClassDefFoundError at ExampleSrcSpockSpec.groovy:21
        Caused by: java.lang.ExceptionInInitializerError at ExampleSrcSpockSpec.groovy:21

com.mkobit.libraryexample.ExampleSrcSpockSpec > create and run a parameterized project FAILED
    java.lang.NoClassDefFoundError at ExampleSrcSpockSpec.groovy:21
        Caused by: java.lang.ExceptionInInitializerError at ExampleSrcSpockSpec.groovy:21

com.mkobit.libraryexample.LibraryResourceStepSpec > libraryResource can load resources in library FAILED
    java.lang.NoClassDefFoundError at LibraryResourceStepSpec.groovy:13
        Caused by: java.lang.ExceptionInInitializerError at XStream.java:811

com.mkobit.libraryexample.VarsExampleJunitTest > testing library that uses declarative pipeline libraries FAILED
    java.lang.NoClassDefFoundError at VarsExampleJunitTest.groovy:14
        Caused by: java.lang.ExceptionInInitializerError at XStream.java:811

com.mkobit.libraryexample.VarsExampleJunitTest > testing library function FAILED
    java.lang.NoClassDefFoundError at VarsExampleJunitTest.groovy:14
        Caused by: java.lang.ExceptionInInitializerError at XStream.java:811

I'm running this with Microsoft JDK 17.0.14.7 on Windows 11.

Can you tell me if there's anything I should do differently? Would be nice to get this working as a baseline, then I can move on to my own scripts.