Cleaned up default separator and newline preferences

Both import and export ASCII use same newline and
column separator values from preference window

Windows newline should default to CRLF

Refs #7573
Correct fix for setting CRLF as default EOL on Windows

Refs #7573
Added some tool tips for less intuitive preferences

Refs #7573
Merge branch 'bugfix/7573_review_preferences' into develop