Move files from src/ to src/nvim/.
- src/nvim/ becomes the new root dir for nvim executable sources.
- src/libnvim/ is planned to become root dir of the neovim library.

The old version required to change the range given to :w for each new
test. Now a new buffer is used instead.

If this backslash is here and USE_VALGRIND is defined, valgrind complains that "else" is not a command.

Problem:  Using just "$" does not cause an error message.
Solution: Check for empty environment variable name.
          (Christian Brabandt)

https://code.google.com/p/vim/source/detail?r=00228400629e28384f7f52556c3c119ba0d0a44d

Problem:  Using exists() on a funcref for a script-local function
          does not work.
Solution: Translate <SNR> to the special byte sequence.
          Add a test.

https://code.google.com/p/vim/source/detail?r=1a5ed2626b26a982e307a206572121a557adf709

Problem:  CTRL-U in Insert mode does not work after using a cursor key.
          (Pine Wu)
Solution: Use the original insert start position. (Christian Brabandt)

https://code.google.com/p/vim/source/detail?r=81c26975e8f9dc7435353581346542409403f296

Problem:  Test 62 fails.
Solution: Set the language to C. (Christian Brabandt)

https://code.google.com/p/vim/source/detail?r=8f84e906d454a95d3167678a745dde9de442b604

Problem:    The string returned by submatch() does not distinguish between a
            NL from a line break and a NL that stands for a NUL character.
Solution:   Add a second argument to return a list. (ZyX)

https://code.google.com/p/vim/source/detail?r=a63d0cd691dc925283815d17d62f4e948d723a59

Problem:    Can't call a global function with "g:" in an expression.
Solution:   Skip the "g:" when looking up the function.

https://code.google.com/p/vim/source/detail?r=8ec9d2196bee0c5108f2d2c196a660a7f4e5f29f