vim: Move autosource of config into ftplugin

Instead of only sourcing the vim config when vimrc or $MYVIMRC (xdg.vim)
is edited, reload always when saving a vim file.
This is a test. But I think it makes sense since I never edit a vim file
that is not sourced by my config in any way. Thus reloading should be
always appropriate.

.config/vim/ftplugin/vim.vim

@@ -0,0 +1,6 @@
+" Source config upon saving vim file.
+" Group to avoid "exponential" reloading. See:
+" https://stackoverflow.com/questions/2400264/is-it-possible-to-apply-vim-configurations-without-restarting
+augroup vimrc_reload
+	autocmd! BufWritePost * source $MYVIMRC | echom "Reloaded" | redraw
+augroup END

.config/vim/vimrc

@@ -159,10 +159,5 @@ else
 	endif
 endif
 
-" Source edited vim config upon saving.
-augroup vimrc
-	autocmd! BufWritePost $MYVIMRC,vimrc source % | echom "Reloaded" | redraw
-augroup END
-
 " Load filetype plugins
 filetype plugin indent on