* changed all the RotatePoint() functions in trigo.{h,cpp} to take a double as the
    angle, which is still in tenths of degrees for now.
  * EDA_TEXT::m_Orient is now double, still in tenths of degrees (for a short while),
    but the double means parsing files and saving them use a different format string.
++pcbnew
  * DRAWSEGMENT::GetStart() and GetEnd() do not operate for S_ARC like they used to.
    They are now simply accessors for m_Start and m_End.  Use DRAWSEGMENT::GetArcStart()
    and GetArcEnd() and GetCenter() for arcs.  specctra_export.cpp was the only
    source file dependent on the old behavior.
  * DIMENSION::m_Text is now contained, not dynamically allocated.
  * more kicad_plugin work.