Version 0.2

K.vim now evolves to be a plugin to let you quickly run external command, and show the result
in a scratch window.

1. press `<leader><leader>` to show explanation of word with call to an external
command `kv`, https://github.com/brookhong/kv

1. press `<space><leader>` to close the scratch window

1. press `<leader>r` to run all scripts in a buffer

1. press `<enter>` to run curren line.