autotools: Allow builds to be done in buildDir

configure is called using a relative path from buildDir
to the project directory and the configure command line
is updated to reflect changes to buildDir.

Change-Id: Ia9e8eef446efd21b6dcedef4668ff03adfd8a20c
Reviewed-by: hjk <hjk121@nokiamail.com>
Reviewed-by: Daniel Teske <daniel.teske@digia.com>

src/plugins/autotoolsprojectmanager/configurestep.h

@@ -103,9 +103,11 @@ public:
 
 public slots:
     void setAdditionalArguments(const QString &list);
+    void notifyBuildDirectoryChanged();
 
 signals:
     void additionalArgumentsChanged(const QString &);
+    void buildDirectoryChanged();
 
 protected:
     ConfigureStep(ProjectExplorer::BuildStepList *bsl, ConfigureStep *bs);