Function: whitespace-cleanup-region

Cleanup some blank problems at region.

The problems cleaned up are:

1. 8 or more SPACEs at beginning of line.
If `whitespace-style' includes the value `indentation':
replace 8 or more SPACEs at beginning of line by TABs, if
`indent-tabs-mode' is non-nil; otherwise, replace TABs by
SPACEs.
If `whitespace-style' includes the value `indentation::tab',
replace 8 or more SPACEs at beginning of line by TABs.
If `whitespace-style' includes the value `indentation::space',
replace TABs by SPACEs.

2. SPACEs before TAB.
If `whitespace-style' includes the value `space-before-tab':
replace SPACEs by TABs, if `indent-tabs-mode' is non-nil;
otherwise, replace TABs by SPACEs.
If `whitespace-style' includes the value
`space-before-tab::tab', replace SPACEs by TABs.
If `whitespace-style' includes the value
`space-before-tab::space', replace TABs by SPACEs.

3. SPACEs or TABs at end of line.
If `whitespace-style' includes the value `trailing', remove
all SPACEs or TABs at end of line.

4. 8 or more SPACEs after TAB.
If `whitespace-style' includes the value `space-after-tab':
replace SPACEs by TABs, if `indent-tabs-mode' is non-nil;
otherwise, replace TABs by SPACEs.
If `whitespace-style' includes the value
`space-after-tab::tab', replace SPACEs by TABs.
If `whitespace-style' includes the value
`space-after-tab::space', replace TABs by SPACEs. See `whitespace-style', `indent-tabs-mode' and `tab-width' for documentation. (fn START END)