Redesign Web API

Normalize Web API method names.
Allow to use alternative Web UI.
Switch Web API version to standard form (i.e. "2.0").
Improve Web UI translation code.
Retranslate changed files.
Add Web API for RSS subsystem.

src/base/utils/string.h

@@ -34,6 +34,7 @@
 
 class QByteArray;
 class QLatin1String;
+class TriStateBool;
 
 namespace Utils
 {
@@ -66,6 +67,9 @@ namespace Utils
 
             return str;
         }
+
+        bool parseBool(const QString &string, const bool defaultValue);
+        TriStateBool parseTriStateBool(const QString &string);
     }
 }