nnoremap <C-Tab> :tabn<cr>  " cycle tabs
nnoremap <C-S-Tab> :tabp<cr>    " cycle tabs backward

nnoremap <C-J> <C-W><C-J>   " no Ctrl-W needed to navigate up
nnoremap <C-K> <C-W><C-K>   " no Ctrl-W needed to navigate down
nnoremap <C-L> <C-W><C-L>   " no Ctrl-W needed to navigate right
nnoremap <C-H> <C-W><C-H>   " no Ctrl-W needed to navigate left