Major updates; allow for dynamic updating
Major updates; allow for dynamic updating

- Don't continuously print non-scrolling text unless it has changed
- Take into account left and right padding when clearing previous text
  when printing in place
- Add "--updatecheck" option
- Add "--grepcommand" option
- Add "--grepsearch" option
- Add "--scroll" option
- Add "--scrollpadding" option
- Make all options that take arguments use action="append" so that they
  are usable with "--grepsearch"
- Split scrollText into more functions
- Consolidate some duplicate code
- Add docstrings to all functions
- Add back flush which is necessary for lemonbar

angelic-sedition/zscroll,angelic-sedition/zscroll