Integrate more selection keys into Annotator

[adammertel]

• SHIFT + PgUp / PgDown -> select to the start / end of paragraph
• SHIFT + CTRL + ↑ / ↓ -> select to the previous / following row (same X position)
• SHIFT + END / HOME -> select to the end / start of the line
• SHIFT + CTRL + END / HOME -> select to the end / start of the document

[davidzbiral]

Prioritizing, didn't realize it does not have priority.

I suggest trying out how these cursor key combinations work in Google Docs - we want the exactly same thing.

[Ptrhnk]

Being resolved separately
SHIFT + PgUp / PgDown #2188
SHIFT + (CTRL) + END / HOME #2193

Closing this as it's being discussed in separate issues