Fleshed out the LSP readme.
Fleshed out the ISP readme.
Fleshed out the DIP readme.
Add Interface Segregation Principle exercise code.
Add Dependency Inversion Principle exercise code.
Remove empty readme file.
Repackage java files.
Actually remove unused java files.
Remove autogenerated Main.java.
Explain job representation's purpose.
Add missing ID and String phrase of ConfidentialPhrase.

I originally accidentally removed those two fields from the class, and that's led to confusion during this exercise on a number of occasions.
Fix a typo in the image prefix URL.
Merge branch 'master' of github.com:theladders/solid-exercises