Fix crash of image_rotation() for +-90 degrees (issue #16)

In the corner cases, sine and cosine values are assigned exactly.
Together with an additional '+1' in the Nx and Ny computation,
this fixes the issue.
resolve conflict
Merge branch 'master' into devel
remove throw from top-level catch convenience macro
reorder code wrt try and output

* build larger Try blocks

* move output behind initialization in order not to generate
  summary output on failure