Log Message:
Update innoextract to 1.6.

innoextract 1.6 (2016-03-24)
 - Added support for Inno Setup 5.5.7 (and 5.5.8) installers
 - Added a --collisions=rename-all option
 - Changed --collisions=rename to omit the suffix for the file that would have \ 
been extracted with --collisions=overwrite instead of the first encountered file
 - Fixed @lang suffix sometimes missing for the first file with the \ 
--collisions=rename option
 - Fixed build error with CMake 3.5
 - Now compiles in C++14 mode if supported
 - Unsafe characters in special constant strings (ie ':' in {code:…}) are \ 
now replaced with '$'
 - Windows: Fixed error message if the source file could not be opened
 - Windows: Fixed progress bar flickering while printing extracted filenames
 - Windows binaries: Fixed crash on platforms without AVX support