Bug 151361 default value for reousrce folder user preference
When user does not sepecify the resourec foler user preference, can we make the current project folder (in IDE) or the current report design file's folder (in RCP) as the default value for the resource folder. This way, by default the current project folder is the resource folder where user can create their libs and images. Also please set the default user preference to be null when BIRT is freshly installed.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/ui/ReportPlugin.java
}
	/**
	 * Return default resouce preference
	 * 
	 * @return String The String of default resource preference
	 */
	public String getDefaultResourcePreference( )
	{
		return getPreferenceStore( ).getDefaultString( RESOURCE_PREFERENCE );
	}
	/**
	 * Return resource preference
	 * 
	 * @return String The string of resource preference
	 */
	public String getResourcePreference( )
	{
		return getPreferenceStore( ).getString( RESOURCE_PREFERENCE );
	}
	/**
	 * set resource preference
	 * 
	 */
	public void setResourcePreference( String preference )
	{
		getPreferenceStore( ).setValue( RESOURCE_PREFERENCE, preference ); 
		CorePlugin.RESOURCE_FOLDER = preference;
	}
	/**
	 * Add View ID into ignore view list.