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Add an example to --time-scale documentation

Reformat text.

Update ChangeLog

Use canonical path of font file.

Don't install FreeSans.ttf if a custom font file is specified.

Document --enable-font-file configure option.

Made command line synopsis consistent.

Clarify that file filters are apply to the full path of the file.

Updated ChangeLog.

Adjusted help message.

Changed version number.