Added missing spaces, fixed example code.

[Faabvk]

Several fixes to the documentation as requested in #35

• Added missing spaces to the explanation of the description argument in create_group() and edit_group()
• Fixed example code
  • create_group() and edit_group(): Made it so GroupMemberFragment objects are passed instead of strings, which would not work.
  • add_members(): GroupMemberFragments were already used here, but they weren't declared correctly when compared to the way wom.py is imported

This PR is to just fix the issues, intending to have another PR to actually allow strings to be passed as group members.

[Jonxslays]

Excellent, thanks for the contribution! ❤️