Bump version to 1.1.0

Bump version to 1.0.0

Extract selection without opening the extract buffer was added

Version 0.3

  vim-buffr plugin version 0.3 required
  * position and buffer name arguments were added to command
  * allow range
  * buffr#open_or_create arguments were changed to dictionary
  * command VExtract was renamed to Extr
  * g:extract_position option was removed

Bump version

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