2015 Holiday Edition

• fixed numerous bugs in bbox methods. There are bugs
  left for layouts that use array references (aref elements)
• new methods for gds_element sref and aref object for fast retrieval
  element properties
• correct error in help text of the gds_element constructor. The
  reflection in an strans record is applied after the rotation.
• print file name when a library is written with write_gds_library.
• Basic/funcs/layerinfo.m optionally returns a vector with layers that
  contain elements
• use 'parfor' to loop over structures in 'Basic/funcs/adjmatrix.m'.
  This has currently no effect in Octave but can speed up functions
  that require the calculation of the structure hierarcy in MATLAB.
• update 'Basic/Contents.m
• update hash functions with newer version of 'gperf'
• fix help text of 'Basic/funcs/topstruct.m'
• corrected help text of Elements/gdsii_*text.m functions.
• update the format of all m-files: 'return' at the end of
  functions is replaced by 'end', removed ';' at the end
  of function definitions.
• update the display methods for elements, structures, and libraries.
• more informative warnings when units are not defined prior to using
  Boolean set algebra operators on elements.