Preparation for python3 and opencv4

The code should be good to be run on python 3
Newer version of opencv - opecv4 can be used
A small rounding error has been fixed

The code still supports python2.7 and opencv2 and at the moment there is only pip release for python2.7.

Focusing Routine Upgraded

CrystaMatch has been tested in a 'real setup' which showed that the focusing routine requires a bit of an improvement.

This release is all about this improvement - fft bandpass filter is used instead of mean value in order to identify the most in focus images.

Documentation update

1.0.3

release notes updated

Default path fix and docs updates

1.0.2

preparation for release 1.0.2

Tag of the release changed

Test with different release tag

v1.0.0

New version of CrystalMatch with build in focusing.