Add support for java-sources in eta repl

[jneira]

With those changes now it is possible to compile and load javaish targets (.java. class. jar) It works at repl startup and with :load (i.e. you can do :load path/to/my.(java|class|jar) on the fly)

Description

Main changes are in Eta.REPL.UI module where it is the calling code to Eta.Main.DriverPipeline to compile files and Eta.REPL.Linker to add them to repl classpath.

How Has This Been Tested?

Manually firing repls with different java source files

Types of changes

• [X] Bug fix (non-breaking change which fixes an issue). Fixes #805
• [X] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Documentation change
• [ ] Test suite change

Checklist:

• [X] I have read the CONTRIBUTING document.

[jneira]

@rahulmutt thanks! not a perfect solution but it can work for now The hard part was reading the source files to guess where to put the code 😆 Now i know a little bit (only a little!) more of ghc flow