renamed: TestTimeline.java -> TestTimeLine.java
refactoring: try to make the code more readable by creating TimeLines class
refactoring: simplify code by deleting unknown user exceptions (behaviour is not specified: now a new timeline is always created for an unknown user)
try to make code more readable by creating Followers class
connect user input translator to Application; renamed UserInputToCommandTranslator -> ConsoleMain
implement message display to be conform with the instructions e.g.: Alice - I love the weather today (5 minutes ago)
add notes
remove dependency on Guava
make groupId consistent with my other interview exercises
add instruction to run the application