Remove unnecessary Non-ASCII characters from source code (#9075)

* Remove unnecessary Non-ASCII characters from source code

Remove unnecessary Non-ASCII characters and replace them with ASCII
characters

* Remove dashes in the @param statement

Remove dashes and place single space in the @param statement to keep
coding style

* misc: more fixes for non-ASCII symbols

* misc: fix non-ASCII symbol in CMake file

how_to_scan_images.markdown: fix grammar mistakes

Improve the readability of the tutorial.

This is at least useful when using an SVM one-class linear classifier, so there are valid use cases.