Fix api metadata function name in docs

The documentation mentions `vim_get_api_metadata`, but the actual function is `vim_get_api_info`
Merge pull request #1473 from alexgenco/patch-1

Fix api metadata function name in docs
vim-patch:7.4.378 #1217

Problem:    Title of quickfist list is not kept for setqflist(list, 'r').
Solution:   Keep the title.  Add a test. (Lcd)

https://code.google.com/p/vim/source/detail?r=v7-4-378
Update README.md
Update README.md