Problem:    The :global command does not work recursively, which makes it
            difficult to execute a command on a line where one pattern matches
            and another does not match. (Miles Cranmer)
Solution:   Allow for recursion if it is for only one line. (closes vim/vim#1760)
https://github.com/vim/vim/commit/f84b122a99da75741ae686fabb6f81b8b4755998

* vim-patch:8.0.0474: the client-server feature is not tested

Problem:    The client-server feature is not tested.
Solution:   Add a test.
https://github.com/vim/vim/commit/15bf76d40be1f1622ff5cc16596c308e76e2ca94

* vim-patch:8.0.0475: not enough testing for the client-server feature

Problem:    Not enough testing for the client-server feature.
Solution:   Add more tests.  Add the remote_startserver() function.  Fix that
            a locally evaluated expression uses function-local variables.
https://github.com/vim/vim/commit/7416f3e73ab2c4e7ae3adc2ff6e70234f7d40d2e

* vim-patch:8.0.0492: a failing client-server request can make Vim hang

Problem:    A failing client-server request can make Vim hang.
Solution:   Add a timeout argument to functions that wait.
https://github.com/vim/vim/commit/81b9d0bd5c705815e903e671e81b0b05828efd9c

Include src/nvim/testdir/test_clientserver.vim changes from
patches 8.0.0477, 8.0.0479.

* vim-patch:8.0.0633: the client-server test is still a bit flaky

Problem:    The client-server test is still a bit flaky.
Solution:   Wait a bit for the GUI to start.  Check that the version number
            can be obtained.
https://github.com/vim/vim/commit/60964f68740b8abcbb2d3f0f3aeade21d1bacb22

Include src/nvim/testdir/test_clientserver.vim changes
from patches 8.0.0507, 8.0.0511.

* vim-patch:8.0.1251: invalid expressin passed to WaitFor()

Problem:    Invalid expressin passed to WaitFor().
Solution:   Check if the variable exists.
https://github.com/vim/vim/commit/d97fbf171ec0e63117813da045d2a1c51a9b6f62

When giving a section, the first candidate selection was not performed.

followup/fixup #8341

Problem:    Giving an error message only when 'verbose' set is unexpected.
Solution:   Give a warning message instead.
https://github.com/vim/vim/commit/f8be461d0284110b321be748fea206d4169b98bb

closes #8674
npm log level may cause unexpected output.

closes #7383
closes #7715

This implements the compromise described in #7383:
* low-priority CursorLine if foreground is not set
* high-priority ("same as Vim" priority) CursorLine if foreground is set

ref d1874ab2821d076397290cc154d87ec2dc352c79
ref 56eda2aa17c80ba380b606f9466f288fb8162dd3

Compare `$VIRTUAL_ENV` to `python_bin`.
This is necessary when `g:python_host_prog` is set to an absolute path,
and looking up `pyname` in `$PATH` yields another result.