Fix Lyo build issues

[berezovskyi]

Description

We have the following problems:

• Kotlin classes from the TRS libs were not covered in the Javadoc; JDK11 fails the build (but more importantly, our users were getting incomplete javadoc JARs)
• SHACLex library is no longer available from Bintray because it shut down
  - SHACLex 0.0.87 is not available in the new repo
  - SHACLex 0.1.x breaks the 0.0.8x API; updates needed (asked for help in Provide an example of how to use inside Java weso/srdf#168)

TODOs

• Update the build to add GH repo credentials to secrets?
• Fix the SHACLex invocation (we should consider building a Scala shim that would be easy to invoke from Java and would not use any advanced Scala features on the outside API)
• Remove use of Bintray by Dokka plugin

Checklist

• This PR adds an entry to the CHANGELOG. See https://keepachangelog.com/en/1.0.0/ for instructions. Minor edits are exempt.
• This PR was tested on at least one Lyo OSLC server or adds unit/integration tests.
• This PR does NOT break the API

Issues

Closes #78; see #80

[berezovskyi]

See https://github.com/weso/shaclexjava/blob/master/src/main/java/es/weso/shaclexjava/Main.java and https://github.com/weso/shaclexjava/blob/master/src/test/java/es/weso/shaclexjava/ValidateTest.java for Scala cats IO use from Java.

[berezovskyi]

Tracking Lyo Validation package retrieval issue in https://bugs.eclipse.org/bugs/show_bug.cgi?id=574043.