v2.10.1: default options, fix of saving backups, UI updates, a more instructive GettingStarted, context menu support in permalink buttons, and more

Changes summary:

• Behavior improvements:
  • Default option values are no longer stored in cookies;
  • Permalink buttons now support context menus (to copy url/open in a new tab/...).
• UI updates (see the visual summary):
  • Colors of inputs are now based on ColorPalette (Background, Foreground);
  • Upgrade wizard now looks better (on mobile devices in the first place, when using with a proper viewport tag):
    • Symmetrical margin for backstage panels (avoid viewport overflow);
    • Shorter and clearer title and subtitle;
    • The upgrade url is now shown without the https:// bit;
    • Borders of wizard buttons are now symmetric (and look better in the dark mode);
  • GettingStarted shadow is now clearer and more instructive, has a link to quickly find custom savers;
  • Tagging, tags blocks now use thick borders instead of solid background color;
  • Preventing multiword tab labels from getting multiline in some cases.
• Fixes:
  • Native backups saving broken in 2.10.0 works again.
• Hackability:
  • tw.options.define(name, defaultValue, description) is now available for plugins;
  • tw.io.getOriginalLocalPath is now available to use and decorate (used in the core);
  • saveMain always passes original to the callback;
  • saveEmpty can be called without posDiv (recalcs if it's not passed) and handles problematic original.
• Infrastructure:
  • jQuery is now a dependency defined by package.json (forced updating 1.8.3 → 1.9.1);
  • removed autotests of a deprecated module (Crypto) duplicating those of direct usage (Encoding).
• Lingo updates (for translations)
• Docs updates include added steps of releasing, replacing Tiddlyspot with Tiddlyhost, minor links and styles updates, removing mentions of the (long gone) Wii browser, and the update of the ~GettingStarted shadow mentioned above.

Acknowledgements for contributions: to @PengjuYan , @simonbaird .

See the full changelog in #299