ulPlaintext: Move styles from ulstyles to 'base'

Styles developed during writing of the tutorial are moved to the 'base' styles/package
Rename ulPlainTextWorkflows to plaintextworkflows-draft

After the Karlsruhe presentation I will completely review the text.
The first version has been written as a draft and as a collection of materials.

So I re-label the existing file as a draft and set up a new document.
While filling up this document (based on the outline of the Karlsruhe script)
I will move material from the draft to the new document and leave the remaining
stuff to be used in further texts
plaintext: Start (introduction)

Rewrite the text along the outline of the Karlsruhe presentation.
Move reused material from the -draft document (and remove unusable material from there).
Leave unused material in the -draft doc for later reuse
plaintext: Start (introduction)

Rewrite the text along the outline of the Karlsruhe presentation.
Move reused material from the -draft document (and remove unusable material from there).
Leave unused material in the -draft doc for later reuse
plaintext: WIP
plaintext: Add minimal-example files
plaintext: WIP
plaintext: WIP
plaintext: Add Schoenberg example
plaintext: WIP
plaintext: Fix schoenberg example
plaintext: WIP

Revise Plain Text chapter
Start  Versioning basics
plaintext: WIP

Complete versioning chapter
plaintext: add Gethsemane example files
plaintext: add Brahms example

used for demonstrating basic LilyPond syntax and Frescobaldi screenshots
plaintext: add Frescobaldi screenshots
.gitignore: ignore lilypond-book files
plaintext: WIP (Frescobaldi)
plaintext: WIP (small changes)
plaintext: Add opus 8-4 Finale example