Bug 821: workaround MSVC 2013 issue with using Base::Base::operator=

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extra : source : 79a32d90365d77bb3600145cfe2ca420b4fd1a65
Fix wrong negative in nullary unit test when extended precision is used (FPU).

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extra : source : d4eb9f762c4bab762cae5744b3192ca4c2fedddd
Fix false negatives in geo_transformations unit tests

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extra : source : 5105d7c51b184443f09f616f1a3b87d3d9a603b9