LADSPA support 0.4.2

Currently I'm working on LADSPA support of comming release 0.4.2

You may add or remove LADSPA effects by using machine properties editor by accessing context menu. It features as well a LADSPA browser. Within you may choose your prefered widget as port control. Currently supported are:

• AgsDial
• GtkSpinButton
• GtkScale
• GtkToggleButton

Future releases may bring more advantages of port controls.