Optional undistortion in point detectors

Merge pull request #90 from UCL/89-optional-undistort

89 optional undistort

Fix multiple dot detection bug

Merge pull request #88 from UCL/87-dot-multiple-points

87 dot multiple points

Add adaptive thresholding to dot detector

82 test dot patterns (#83)

* Add example data from Mock OR

* Linting.

* Issue #82: Add adaptive thresholding and more constructor params.

* Issue #82: Fix unit tests. Minor difference in number of points detected, normally +/- 1, so ok.

* Issue #82: Linting.

* Issue #82: Only use 1 test image from mock OR, too much storage to test them all

* Fix typo in image path

* Linting

Co-authored-by: Matt Clarkson <m.clarkson@ucl.ac.uk>