Strip double quotes from string list sliders
Fix 'edit filter database' slider option for short name functions
Add a new macro function 'ClearBookmarks'
Remove some annoyances from FloatSpin

Usability improvements:
- Select all on TAB or Ctrl+A
- Process RETURN normally

wx.TE_NOHIDESEL effect is still present though: tab navigation can be difficult
with Windows themes on which the caret colour is very similar to the selected
text background.
[Bookmarks at Intervals] Add custom range and clear existing bookmarks option

Closes #18