[Tools/SBS]add "export" attribute to dependency

[GoogleCodeExporter]

The goal of "export" is to not repeat a dependency between sbs.xml

For example :

Without export :

* in Screen/Utils :

<dependency name="boost" version="1.42">
   <libraries>
      <lib>boost_thread</lib>
   </libraries>
</dependency>

* in Screen/Main :

<dependency name="Screen/Utils" version="0.1.0"/>
<dependency name="boost" version="1.42">
   <libraries>
      <lib>boost_thread</lib>
   </libraries>
</dependency>

With export :

* in Screen/Utils :

<dependency name="boost" version="1.42" export="true">
   <libraries>
      <lib>boost_thread</lib>
   </libraries>
</dependency>

* in Screen/Main :

<dependency name="Screen/Utils" version="0.1.0"/>

The method to implement export is to copy the dependency into Screen/Utils 
component.xml

Original issue reported on code.google.com by thoratou@gmail.com on 22 Jul 2010 at 2:37

[GoogleCodeExporter]

Implemented in local, must commit it

Original comment by thoratou@gmail.com on 26 Jul 2010 at 7:05

• Changed state: Started

[GoogleCodeExporter]

implemented and verified

Original comment by thoratou@gmail.com on 27 Jul 2010 at 6:00

• Changed state: Verified