One trivial change required in a unit test

I decided to add the missing constructor to Point and Extent in afw

A test change that can be reverted after fixing afw is meas_astrom testMakeMatchStatistics in two places (look for (*).

After wrapping the Point and Extent Eigen constructors in afw all tests in skymap passed.

This change also allowed me to revert a modification to a test in meas_astrom.

Finally I made some other changes in afw on separate commits (in case you don't want some of them) including (changes are in point.cc and extent.cc unless otherwise noted):

• fix __neq__ -> __eq__ in several wrapper files (I will add these to my "needs test" list)
• use namespace lsst { ... instead of using ...
• stop using pybind11/operators.h
• run clang-format, primarily to break some lines that were too long
• add py::is_operator() in the remaining safe places (not in-place operators)

Two other changes I would be happy to make in afw given your permission:

• Get rid of a long note about SWIG in testCoordinates.py testInPlaceOperators that seems to be obsolete
• Change the two wrapper files to use self and other instead of p/e and o for operator arguments

Looks good. Please feel free to finish cleanup as desired. But make sure py::is_operator does not change the expected behaviour when calling with non implemented type. The Point, Extent interactions were difficult to get right. Also please document any subtleties that you encounter such as when py::is_operator is deliberately not used.

I rebased afw into 3 clean commits: fix __neq__, wrap the Eigen constructor of Point and Extent and modernize the point and extent wrappers. The latter includes standardizing the names for operators (which were quite disparate even within each file, and sometimes used "e" for a Point and "p" for an Extent) and removing the one SWIG comment in testCoordinates.py.