2.3.1 Send mode, sorting, clear filter UI

New features:

• #34 One of the oldest feature requests finally done - there is a button to the top right to clear all filters at once
• #39 Added a combo box to the top right to select which sort order you prefer. The duplicate name search now does no longer force name sorting, because you
  can now select it anyway.
• #234 Added a combo box below the patch grid to select the send mode. Auto is what was before, send sysex only if position in synth
  is not known. Now you can force it to always send sysex, or to always send only program change (which fails if no position known).
• #326 The About Dialog now contains a link to the homepage.
• #327 Added missing test files for Python development to the Windows installer

Synths:

• Yamaha reface CP: New adaptation contributed by @milnak. Many thanks!
• Roland D50: Some progress made on the adaptation, but there are still some problems loading banks. Help appreciated!

Bug fixes:

• #322 Fixed migration problem for some old databases, most notably the database published with all the Ensoniq VFX patches.
• #325 Fixed rename of patch impossible if adaptation had implemented nameFromDump() but not renamePatch(). Now, when only nameFromDump() is
  implemented any rename will change the name in the database, which overrides the stored patch name.
• Updated link to JUCE documentation, as this is no longer with ROLI