Improve "Learning Emacs Lisp" doc

- split up into different sections, accommodate people just starting
  out with Emacs a bit more
- add installation instructions for starter kits
- add Doom Emacs starter kit for people switching from vim
- reference style guide and coding conventions

closes exercism#198
works on exercism#18 (exercism#18 (comment))

Author: fapdash

docs/LEARNING.md

@@ -1,10 +1,69 @@
 # Learning
 
+## Starting out with Emacs
+
 So you've installed Emacs. Now what?
 
 Well, you can start the tutoral by pressing `C-h t`, and that's not a bad place
-to start. If you're completely new to Emacs, the [Emacs Prelude](http://batsov.com/prelude/) package offers a
+to start. The tutorial will teach you the basics of editing, searching, and navigation in Emacs.
+
+If you're completely new to Emacs, it can make sense to grab a starter kit,
+which comes with a set of configurations and packages already set up.
+
+The [Emacs Prelude](http://batsov.com/prelude/) package offers a
 nice set of sensible defaults and packages.
+To install Emacs Prelude run the following in a terminal:
+
+```
+curl -L https://github.com/bbatsov/prelude/raw/master/utils/installer.sh | sh
+```
+
+and make sure to check out the [installation guide](https://prelude.emacsredux.com/en/latest/installation/) for further instructions.
+
+
+If you are familiar with vim you might be interested in the [Doom Emacs](https://github.com/doomemacs/doomemacs) starter kit, which integrates vim emulation powered by [evil-mode](https://github.com/emacs-evil/evil).
+To install Doom Emacs run the following in a terminal:
+
+```
+git clone --depth 1 https://github.com/doomemacs/doomemacs ~/.emacs.d
+~/.emacs.d/bin/doom install
+```
+
+and make sure to check the [installation guide](https://github.com/doomemacs/doomemacs#install) for further instructions.
+
+## Setting up syntax checking and linting
+
+Setting up syntax checking and linting with [Flycheck](https://www.flycheck.org/en/latest/) is recommended.
+
+If you don't already have added the [MELPA](https://melpa.org/) repositories to your Emacs, do this by adding the following to your [init file](https://www.flycheck.org/en/latest/glossary.html#term-init-file)
+
+```elisp
+(require 'package)
+
+(add-to-list 'package-archives
+             '("MELPA Stable" . "https://stable.melpa.org/packages/") t)
+(package-initialize)
+(package-refresh-contents)
+```
+
+Installation and setup of Flycheck without [use-package](https://github.com/jwiegley/use-package) is done by adding the following to your [init file](https://www.flycheck.org/en/latest/glossary.html#term-init-file)
+
+```elisp
+(package-install 'flycheck)
+(add-hook 'after-init-hook #'global-flycheck-mode)
+```
+
+Installation and setup of Flycheck with [use-package](https://github.com/jwiegley/use-package) is done by adding the following to your [init file](https://www.flycheck.org/en/latest/glossary.html#term-init-file)
+
+```elisp
+(use-package flycheck
+  :ensure t
+  :init (global-flycheck-mode))
+```
+
+For further information and trouble shooting please check the [Flycheck documentation](https://www.flycheck.org/en/latest/user/troubleshooting.html).
+
+## Learning Emacs Lisp
 
 The best documentation on Emacs Lisp is... shipped with Emacs itself!
 to access the
@@ -17,3 +76,9 @@ it [online](https://www.gnu.org/software/emacs/manual/elisp.html).
 If you are brand new to Elisp, you can read the
 [Introduction to Emacs Lisp](http://www.emacswiki.org/emacs/EmacsLispIntro),
 which is opened the same way.
+
+## Emacs Lisp best practices and conventions
+
+The Emacs Manual contains a section on Emacs Lisp [Coding Conventions](https://www.gnu.org/software/emacs/manual/html_node/elisp/Coding-Conventions.html).
+
+There is also a community driven [Style Guide](https://github.com/bbatsov/emacs-lisp-style-guide) maintained on GitHub.