✨✨ CLI Command cleanup ✨✨

This PR cleans up the `Command` classes in the CLI, introducing a
`DatabaseCommand` class for the commands operating on a database,
and a `getCommandLineParser` command to centralize the arguments
parsing and validation.

The opening of the database based on the CLI arguments and options
is now centralized in `DatabaseCommand.execute`, making it easy to
add new database opening features (like YubiKey support for the CLI).

Also a couple of bugs fixed:
  * `Create` was still using `stdout` for some error messages.
  * `Diceware` and `Generate` were not validating that the word count was an integer.
  * `Diceware` was also using `stdout` for some error messages.

src/cli/Remove.h

@@ -18,17 +18,15 @@
 #ifndef KEEPASSXC_REMOVE_H
 #define KEEPASSXC_REMOVE_H
 
-#include "Command.h"
+#include "DatabaseCommand.h"
 
-#include "core/Database.h"
-
-class Remove : public Command
+class Remove : public DatabaseCommand
 {
 public:
     Remove();
     ~Remove();
-    int execute(const QStringList& arguments) override;
-    int removeEntry(Database* database, const QString& databasePath, const QString& entryPath, bool quiet);
+
+    int executeWithDatabase(QSharedPointer<Database> db, QSharedPointer<QCommandLineParser> parser);
 };
 
 #endif // KEEPASSXC_REMOVE_H