Imported upstream 4286:afcc61d24129 - patch 892
Merge branch 'master' into merge-upstream

Conflicts:
	src/os_mswin.c
	src/vim.h

* Upstream Vim moved some windows clipboard code around
Fix windows clipboard after upstream merge

- When merging with upstream -892 the build for
  windows broke down because some of the clipboard code
  moved out os_win32.c to winclip.c.
- This commit updates CMakeLists.txt with winclip.c and
  fixes some missing defines that went unchecked in the
  merge.
Update configure script