Add the original ImageJ.iss

This is the file Wayne used for his releases.
Avoid DOS line endings

We're in the 21st century now, after all.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Adjust install.iss to conform to ImageJ.iss

This is really more of a merge between the two of them, keeping the
best of both worlds.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>