feat: Consistent and sensible layout_config (#922)

* feat: Consistent and sensible layout_config

* [docgen] Update doc/telescope.txt
skip-checks: true

* [WIP]: Thu 17 Jun 2021 03:36:44 PM EDT

* [WIP]: Thu 17 Jun 2021 03:38:11 PM EDT

* layout_default -> layout_defaults

* remove options from bug repot

* Conni2461 suggestions: part 1

* [docgen] Update doc/telescope.txt
skip-checks: true

* Conni2461 suggestions: part 2

* [docgen] Update doc/telescope.txt
skip-checks: true

* Linting

* Improve deprecation checks

- Move `layout_defaults` handling to `deprecated.lua`
- Check for "layout keys" outside of `layout_config` on `setup`

* fixup: Just add a few more words

Co-authored-by: Luke Kershaw <35707277+l-kershaw@users.noreply.github.com>
Co-authored-by: Github Actions <actions@github>

.github/ISSUE_TEMPLATE/bug_report.md

@@ -88,37 +88,5 @@ Plug 'nvim-telescope/telescope.nvim'
 call plug#end()
 
 autocmd VimEnter * PlugClean! | PlugUpdate --sync | close
-lua << EOF
-
-require('telescope').setup{
-  defaults = {
-    vimgrep_arguments = {
-      'rg',
-      '--color=never',
-      '--no-heading',
-      '--with-filename',
-      '--line-number',
-      '--column',
-      '--smart-case'
-    },
-    prompt_position = "bottom",
-    prompt_prefix = ">",
-    selection_strategy = "reset",
-    sorting_strategy = "descending",
-    layout_strategy = "horizontal",
-    layout_defaults = {},
-    file_ignore_patterns = {},
-    shorten_path = true,
-    winblend = 0,
-    width = 0.75,
-    preview_cutoff = 120,
-    results_height = 1,
-    results_width = 0.8,
-    border = {},
-    borderchars = { '─', '│', '─', '│', '╭', '╮', '╯', '╰'},
-    color_devicons = true,
-    use_less = true,
-  }
-}
-EOF
+lua require('telescope').setup()
 ```