build: no need to quote the paths in CMake, it will do it automatically
build: only manipulate out if getting the timestamp was successful

This fixes an issue seen in #1548, though the real problem is something
different.
deps: Update lua client
clipboard: support separate '+' and '*' clipboards
clipboard: handle linewise/charwise selections correctly
clipboard: clean up unnamedclip logic
options: change "unnamedclip" back to "clipboard=unnamed/unnamedplus"

This allows to configure which of '*' and '+' should be used for
the unnamed clipboard, and is consistent with vim.
clipboard: better error messages when provider not available
clipboard: add functional test
clipboard: fix `let @+ = ...` and add test
eval_has_provider: search autoload scripts same order as call_func
Merge pull request #1599 from jszakmeister/gitrev-fixes

Some simple fixes to GetGitRevisionDescription.cmake.
docs: remove unnamedclip option
Merge pull request #1182 from bfredl/clipboard

clipboard: support separate +/* clipboards, linewise copy/paste and add tests
docs: More consistent descriptions of rpc*() funcs

- Remove note about how {channel} is rpcstop's only argument; just
  mention {channel} at the beginning like the other descriptions.
- Small grammar fixes
docs: Misc. improvements to job_control/msgpack

- Rewrote a few sentences for clarity/brevity
- Remove usage of 'you'
- Various spelling/grammar fixes
- Reflowed all changed paragraphs accordingly
- Remove trailing whitespace