Added install images as dependency to html_.

doc/Jamfile

@@ -6,26 +6,17 @@ import asciidoctor ;
 
 html index.html : index.adoc  ;
 
-install html_ : index.html : <location>html ;
+install images : $(images) : <location>html/images ;
+install html_ : index.html : <location>html : <dependency>images ;
 
 pdf cobalt.pdf : index.adoc ;
 explicit cobalt.pdf ;
 
 install pdf_ : cobalt.pdf : <location>pdf ;
 explicit pdf_ ;
 
-install images
-    :
-        images/awaitables.png
-        images/generators1.png
-        images/generators2.png
-        images/lazy_eager1.png
-        images/lazy_eager2.png
-        images/stackless1.png
-        images/stackless2.png
-    :
-        <location>html/images
-    ;
+
+
 
 alias boostdoc ;
 explicit boostdoc ;

doc/background/stackless.adoc

@@ -45,7 +45,7 @@ ifndef::generate-diagram[]
 image::stackless1.png[]
 endif::[]
 
-Coroutines can be implemented a stackful, which means that it allocates a fixes chunk of memory and stacks function frames similar to a thread.
+Coroutines can be implemented as stackful, which means that it allocates a fixes chunk of memory and stacks function frames similar to a thread.
 C++20 coroutines are stackless, i.e. they only allocate their own frame and use the callers stack on resumption. Using our previous example:
 
 [source,cpp]