Improve calendar-navigation on organizer and events page (Z#177488) (#2373)

* hide icons for calendar-types and improve layout-breakpoints in calendar top-nav

* change month-selector to one dropdown "date"and redirect old URLs to new date-based URLs

* change week calendar to one dropdown "date“ and redirect old URLs to new date-based URLs

src/pretix/static/pretixcontrol/scss/_forms.scss

@@ -22,6 +22,10 @@ td > .form-group > .checkbox {
   padding-top: 7px;
 }
 
+.form-inline .form-control {
+  max-width: 100%;
+}
+
 .has-success .form-control {
   border-color: #cccccc;
 }

src/pretix/static/pretixpresale/scss/_forms.scss

@@ -33,6 +33,10 @@ a.btn, button.btn {
   margin-right: 10px;
 }
 
+.form-inline .form-control {
+  max-width: 100%;
+}
+
 .form-control.is-focused {
   $color-rgba: rgba(red($input-border-focus), green($input-border-focus), blue($input-border-focus), .6);
   border-color: $input-border-focus;

src/pretix/static/pretixpresale/scss/main.scss

@@ -396,7 +396,7 @@ h2 .label {
 }
 
 .event-list {
-    margin-top: 15px;
+    margin-bottom: 15px;
     border-top: 1px solid $table-border-color;
 
     .row {