Merge pull request #6 from feraxhp/concurrent

## ASYNC is here
* ++ concurrent process
* *+ version handling
* ++ option for change the number of concurrent operations
* ++ indicator for images being converted

## Improve user feedback
* ++ error count in batch conversion
* *+ cleaner output when just 1 image is converted

*! msi size

 ++ windows msi installer, ++ logos

 ++ release workflows