feat: use ast to parse doc more quickly (#68)

It would be amazing to avoid execution issues when looking at documentation. 
Plus, no execution means better performance. Abstract Syntax Tree (ast) are a way to parse code without evalualting or even compiling it. We can then travese those tree structure to find the information we need.

New algorythm
1. get the **script block** and **template block** from the **Single File Component** (SFC) using vue-template-compiler.parse
1. get the **AST** from this **script block** using `recast` and `@babel/parser`
1. get the **exported subtree** of this **AST** which will contain the documented component
1. get the **displayName**, **props** and **methods** from this **AST** (to get types, default and parameter names) 
1. get the **docblocks** out of the **script block** or the **AST**
1. merge the **docblocks** with the **props** and **mehods**
1. add the **slots** documentations to the documentation object

- [x] General Scaffolding
- [x] Props Handler
- [x] Methods and params Handler
- [x] Component description, name and comment Handler (extra tags to be handled)
- [x] Slots Handler
- [x] Mixins Handler
- [x] Events handler
- [x] `extends` property of a component (implement like a mixin)
- [x] jsx parser
- [x] typescript parser
- [x] get rid of the `react-docgen` dependency (only used for `resolveToValue`)
- [x] rewrite the lib in typescript
- [x] deal with require mixins and extends
- [x] use typescritpt/flow parsing to determine type of arguments
- [x] enable parsing of Decorated class type components `vue-property-decorator`

fixes #73, #58, #53, #50, #44, #33, #27, #25, #23, #11, #9 

[BREAKING CHANGE]: `comment` properties (containing the full extract of each leading comment (with all the `/**` and the ` * `) are entirely removed from the documentation as they were not useful. Use `description` or `tags` instead.

[BREAKING CHANGE]: Events that are not commented near their call will not anymore be parsed. If you want to document events, do it as a leading comment of your event call

Author: elevatebart

.babelrc

@@ -1,3 +1,4 @@
 /dist/
 node_modules/
 .eslintcache
+coverage/

.eslintignore

@@ -1,2 +1 @@
-**/*.test.js
-dist/**/*.js
+dist/

.eslintrc

@@ -1,7 +1,7 @@
 {
   "printWidth": 100,
   "singleQuote": true,
-  "trailingComma": "es5",
+  "trailingComma": "all",
   "semi": false,
   "bracketSpacing": true,
   "useTabs": false,