fixes for small things in chapters

Author: ofZach

chapters/cplusplus_basics/chapter.md

@@ -39,7 +39,7 @@ You will notice right away that there is an editor already containing some code,
 
 A menu drops down with a list of programming languages. Please choose C++14, shown in Figure 5.
 
-![Figure 5](images/choose-c11.png "Figure 5")
+![Figure 5](images/choose-c14.png "Figure 5")
 
 Notice that the code in the editor changed, and looks something like figure 6.
 

chapters/cplusplus_basics/images/choose-c14.png

@@ -56,7 +56,7 @@ This way the loading of the image happens simultaneously to our update/draw loop
 
 Now, how do we know when our image is loaded? The thread will run separately from the main thread of our application:
 
-![Simple Thread](images/simple_thread.svg "Simple Thread")
+![Simple Thread](images/simple_thread.png "Simple Thread")
 
 As we see in the image the duration of loading of the image and thus the duration of the call to threadedFunction is not automatically known to the main thread. Since all our thread does is load the image, we can check if the thread has finished running which will tell us that the image has loaded. For that ofThread has a method: `isThreadRunning()`: