Allow longer sentences

[ghost]

The style checker checks whether sentences are long. It outputs messages at the following sentence lengths currently:

• a warning:
  • all current versions: 26 words or more
• an error:
  • packaged version: 33 words or more
  • development version: 35 words or more

What are the best values to set these to?

@taroth21 any concrete ideas here? (It was your issue #49 that prompted this.*)

• taroth: "[...] In addition, the current value set for sentence lengths that trigger a warning or a message is IMHO too short."