Merge Tag and Label tables

[rolymaz]

I propose the Tag table and Label table are merged into one. This will greatly simplify the database schema and allow for easier data extraction and analysis. Looking at the code, it is difficult to determine how a tag is actually created. It looks like it is based off the Label. Why is the same info saved seperately, with a different Id? Merging this into one table should make the data easier to work with.