OpenGl_LineAttributes - drop display lists for stipple lines.
OpenGl_Context - add methods OpenGl_Context::SetTypeOfLine() and OpenGl_Context::SetLineWidth() to setup line aspects.
OpenGl_ShaderManager::prepareStdProgramFlat() - support new bit OpenGl_PO_StippleLine.
vaspects command - add -setlinetype option.
OpenGl_Element destruction and resource deallocation methods now accept
a pointer to OpenGl_Context instead of a handle to avoid double deletion
of the context.
