v1.18.0

Bugfixes:
- don't miss start of next file with --word-diff
  commit a64b3812b333e68b79198b637c3682a6016a580a
- no linenumbers with --word-diff even if code is indented with spaces
  (they should not be displayed because they may be wrong)
  commit f6803d2db8048f46a5834793d24744ed32391339
- { and } work with --word-diff
  commit 8ea8ded898b449b11c70827e5fd73c7808a4173a

New features:
- linenumber --cycle  (mapped to key #)
  commit ce8ad1a418037f7f4f4c07001258436024efe463

Changes:
- print line number format on change
  commit 104787302cf673656bc5b748b73f8137a978e6db