Guava dependency resolution bug

[fwcd]

There is an issue with the Guava dependency.

When including Guava explicitly as dependency...

• The tests will pass
• The language server will complain at runtime that the LSP4J/Xtext Guava dependency is missing and fail when trying to provide code completion

When omitting an explicit Guava listing...

• The tests will fail throwing NoSuchMethodExceptions
• The language server will work

Currently the Guava dependency is omitted, so the application will work but many of the tests do not work currently. This should obviously be resolved somehow.

[fwcd]

Fixed.