Advertising server

Instructions

• Project can be build using ./gradlew build command. Unit tests will be run after building.
  
• Integration tests can be run using ./gradlew integrationTest command.
  You can run ./gradlew build integrationTest command to build and to run integration tests.
  
• Application can be run with java -jar build/libs/advertising-1.0-SNAPSHOT.jar command.
  
• You can pass new path of the directory that contains CSV files for import while running the application using java -jar build/libs/advertising-1.0-SNAPSHOT.jar --dbDirectory="[PATH TO DIRECTORY]" command.
  For example path can be "./db" if you run this command in the project directory.

Notes:

1. Double data type is used for Revenue field. Double doesn't handle power of 10 well.
   So when we need accurate results, we need to use BigDecimal type.
   However it requires much more memory and hence CPU than double, so when these resources are important we can sacrifice some accuracy.
   I used double since there is no formal requirement and for simplicity.

TODO:

1. Cover ReportsController with unit tests.
   Integration tests cover it fully now but it will be great to have unit tests too. I left just integration tests here to save time.