Issue eclipse-cdt#167 - Core Build Makefile project build output folder.

* Issue Issue eclipse-cdt#167 was partly solved by PR eclipse-cdt#192 (commit 7911ac8).
  This change fixes the problem that after closing and opening a
  Makefile project the wrong build output location was used for the
  default Run configuration.
  The cause was that StandardBuildConfiguration.buildContainer was
  null after opening the project.
* Fixed the problem that the output binary could not be found during
  launching when the user set the Build Output Location to "Build in
  project directory".

Fixes eclipse-cdt#167

build/org.eclipse.cdt.make.core/src/org/eclipse/cdt/make/core/MakefileProjectGenerator.java

@@ -84,7 +84,7 @@ public void generate(Map<String, Object> model, IProgressMonitor monitor) throws
 			}
 		}
 
-		entries.add(CoreModel.newOutputEntry(buildFolder.getFullPath()));
+		entries.add(CoreModel.newOutputEntry(project.getFullPath()));
 		CoreModel.getDefault().create(project).setRawPathEntries(entries.toArray(new IPathEntry[entries.size()]),
 				monitor);
 	}