Add a customizable logo to QR (#1955)

* add QR_LOGO variable
* add logo to images folder
* css for overlaying logo on qr
* qr url on settings
* add qr url to global env
* add QR url input on theme tab in adminUI
* new component added
* use svg
* remove white border around logo in the QR

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Co-authored-by: Pavol Rusnak <pavol@rusnak.io>
Co-authored-by: dni ⚡ <office@dnilabs.com>

lnbits/helpers.py

@@ -49,6 +49,7 @@ def template_renderer(additional_folders: Optional[List] = None) -> Jinja2Templa
     t.env.globals["SITE_TAGLINE"] = settings.lnbits_site_tagline
     t.env.globals["SITE_DESCRIPTION"] = settings.lnbits_site_description
     t.env.globals["LNBITS_THEME_OPTIONS"] = settings.lnbits_theme_options
+    t.env.globals["LNBITS_QR_LOGO"] = settings.lnbits_qr_logo
     t.env.globals["LNBITS_VERSION"] = settings.version
     t.env.globals["LNBITS_ADMIN_UI"] = settings.lnbits_admin_ui
     t.env.globals["LNBITS_NODE_UI"] = (