Add bats unit testing to repository

Will recursively look for `*.bats` files and run them with bats-core test suite. Simple sample unit tests for existing scripts are included in `.config/shell/rc.d/test`.

.config/nvim/init.vim

@@ -64,6 +64,7 @@ Plug 'stephpy/vim-yaml'
 Plug 'mhartington/nvim-typescript', {'for': 'typescript','do': './install.sh'}
 Plug 'fatih/vim-go', { 'do': ':GoUpdateBinaries' }
 Plug 'deoplete-plugins/deoplete-go', { 'do': 'make'}
+Plug 'aliou/bats.vim'
 
 " HTML Workflow
 Plug 'valloric/matchtagalways', { 'on': [] }