Make project setup scripts

[jonasKjellerup]

The project has a lot of components that need to be built before development can be done. To simplify this process having a setup script would be ideal. It should cover the following tasks:

• [x] Per default fetch prebuilt songbook (depends on #38) - flag to disable. (This is to avoid requiring a pandoc install)
• [ ] Option to build songbook from source (requires pandoc)
• [ ] Build relevant submodules.
• [x] Install all dependencies.

[LowkeyCoding]

When #61 is done pandoc will no longer be required to build the songbook.