Importer Fixes + typo fix

Several bug fixes covered in this MR separated into commits.

CADSTAR importer:

• Schematic:

  • Parse missing TERMATTR node
  • Fix loading of graphical arc segments (Previously they were loaded as a straight line, now piece-wise approximation)
  • Fix orientation of components (Better logic and also handle different units in older CADSTAR versions)
  • Fix Loading of page numbers (Need to keep track of the hierarchy path in order to assign the page number)
  • Parse SCALE token in Symbol and warn user this is not supported (Fixes #6463 (closed))
  • Fix loading of buses (Use BUS_ALIAS and place bus label)
  • Fix loading of schematic sheet pins and orientation of labels (Find the intersection between the wire and the sheet and place the sheet pin there, Find the intersection between the wire and the sheet and place the sheet pin there)

• PCB:

  • Correctly load the pad numbers as per the original design. E.g. FPGA pins now loaded as A1, A2, B1, etc. instead of 1,2,10, etc.
  • Fix loading of old CADSTAR designs and Do Not Keep Text Upright (Fixes #6437 (closed))

• PCB and Schematic:

  • Only load the master variant (This fixes the problem of having duplicate items when loading a design with variants such as the ones found here)
  • Fix duplicate KIID for loaded elements (Don't use clone to copy an EDA_ITEM. Use Duplicate(). Create Duplicate() method in LIB_PART)

Project importer (EAGLE and CADSTAR):

• Do not rebuild the netlist or reannotate after import (Fixes #6383 (closed))

Miscellaneous:

• Fix typo in zone filling progress reporter. "insulated" -> "isolated"