db: add random data generation

- add .txt files and methods to randomise system data
- found in SampleDataGenerator.java
data generator: cleanup
db: add methods to generate random data

- able to generate any number of any data items
- read from .txt files
- implemented into SampleDataGenerator
Merge branch 'randomization'

Conflicts:
	Retail Storage System.db
Merge branch 'master' of ssh://github.com/d14123081/team4

Conflicts:
	test/team4/retailsystem/integration/SampleDataGenerator.java
db: update db with more items

- use new random data generator