Delete changelog.develop file

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CHANGELOG.develop

--*- mode: org -*-
-
-This file containes the change log for the next major version of Spacemacs.
-
-* Release 0.201.x
-** 0.201.0
-*** Hot new feature
-- Introduction of =spacemacs-purpose= layer in charge of handling Emacs windows
-  assignation for actions opening new buffers. This layer brings more
-  consistency to windows creation by giving them a purpose (i.e. =edit=,
-  =help=, etc...)
-  (thanks to bmag)
-*** New layers
-- =spacemacs-purpose= in =+spacemacs= directory (thanks to bmag)
-*** Layer changes
-**** Org
-- Move clock related key bindings to ~SPC a o k~
-- Add key bindings ~SPC a o k i~ to clock in last and ~SPC a o k j~
-  to jump to current clock (thanks to darkfeline)