multiple pages: change Unicode characters to ASCII (#2802)

Change Unicode characters to ASCII:

- non-breaking spaces (\xc2\xa0) to normal spaces (\x20)
- apostrophes (there are only 2 Unicode apostrophes, all others are already ASCII)
- hyphen (−) to minus (-)
- fix wording (STD‐OUT to "standard output")

pages/osx/ditto.md

@@ -6,7 +6,7 @@
 
 `ditto {{path/to/source}} {{path/to/destination}}`
 
-- Print a line to the Terminal window for every file that’s being copied:
+- Print a line to the Terminal window for every file that's being copied:
 
 `ditto -V {{path/to/source}} {{path/to/destination}}`