Fix TypeError in Python 3

[Pikamander2]

Fix TypeError in Python 3 (can only concatenate str (not "numpy.float64") to str)

[Pikamander2]

I was trying out ImageAI for the first time and noticed that one of the examples throws a TypeError when you try to run it.

The eachProbability variable needs to be cast into a string before concatenating it, so I wrapped a call to str() around it.

I also cast the eachPrediction variable to a string just to be safe, although that may not be necessary.

[codecov]

Codecov Report

Merging #590 into master will decrease coverage by 38.17%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           master     #590       +/-   ##
===========================================
- Coverage   48.83%   10.66%   -38.18%     
===========================================
  Files          63       24       -39     
  Lines        5856     3450     -2406     
===========================================
- Hits         2860      368     -2492     
- Misses       2996     3082       +86