Fix typos found by codespell (#70)

src/capture/widget/buttonhandler.cpp

@@ -69,7 +69,7 @@ size_t ButtonHandler::size() const {
     return m_vectorButtons.size();
 }
 
-// UpdatePosition updates the position of the buttons arround the
+// UpdatePosition updates the position of the buttons around the
 // selection area. Ignores the sides blocked by the end of the screen.
 // When the selection is too small it works on a virtual selection with
 // the original in the center.

src/cli/commandlineparser.cpp

@@ -65,7 +65,7 @@ QString optionsToString(const QList<CommandOption> &options,
         }
         dashedOptionList << joinedDashedOptions;
     }
-    // check the lenght of the arguments
+    // check the length of the arguments
     for (auto const &arg: arguments) {
         if(arg.name().length() > size)
             size = arg.name().length();

src/main.cpp

@@ -79,7 +79,7 @@ int main(int argc, char *argv[]) {
     CommandLineParser parser;
     // Add description
     parser.setDescription(
-                "Powerfull yet simple to use screenshot software.");
+                "Powerful yet simple to use screenshot software.");
     parser.setGeneralErrorMessage("See 'flameshot --help'.");
     // Arguments
     CommandArgument fullArgument("full", "Capture the entire desktop.");