Remove vim-sensible

vim-sensible includes and old matchit.vim which interfears with
vim-matchup and sets some defaults which are then overridden in
plugins/settings.vim. Remove vim-sensible and document the retained
settings.

vimrc

@@ -4,6 +4,13 @@ scriptencoding 'utf-8'
 " Set leader to space
 let g:mapleader = ' '
 
+if has('autocmd')
+  filetype plugin indent on
+endif
+if has('syntax') && !exists('g:syntax_on')
+  syntax enable
+endif
+
 " Plugins
 call plug#begin('~/.vim/bundle')
 
@@ -104,8 +111,6 @@ Plug 'tpope/vim-vinegar'
 Plug 'tpope/vim-abolish'
 " vim-unimpaired - for pairs of tasks
 Plug 'tpope/vim-unimpaired'
-" vim-sensible - sane default settings
-Plug 'tpope/vim-sensible'
 " vim-speeddating - sane date manipulation
 Plug 'tpope/vim-speeddating'
 " vim-endwise - wisely add end{if,function}, fork with cmake support