Limit composer package to `src/`

While there is value in providing those, they also clutter IDE auto-complete feature.
Now they users can opt-in to download them via `--prefer-source` flag.

Closes #908
Closes #1424

.gitattributes

@@ -1,4 +1,16 @@
-/tests export-ignore
-README.md export-ignore
 *.min.js binary
+/.gitattributes export-ignore
 /.github export-ignore
+/.gitignore export-ignore
+/.php_cs.dist export-ignore
+/.sami.php export-ignore
+/.scrutinizer.yml export-ignore
+/.travis.yml export-ignore
+/CHANGELOG.PHPExcel.md export-ignore
+/bin export-ignore
+/composer.lock export-ignore
+/docs export-ignore
+/mkdocs.yml export-ignore
+/phpunit.xml.dist export-ignore
+/samples export-ignore
+/tests export-ignore

CHANGELOG.md

@@ -19,6 +19,7 @@ and this project adheres to [Semantic Versioning](https://semver.org).
 
 - Drop support for PHP 7.1, according to https://phpspreadsheet.readthedocs.io/en/latest/#php-version-support
 - Drop partial migration tool in favor of complete migration via RectorPHP [#1445](https://github.com/PHPOffice/PhpSpreadsheet/issues/1445)
+- Limit composer package to `src/` [#1424](https://github.com/PHPOffice/PhpSpreadsheet/pull/1424)
 
 ## [1.12.0] - 2020-04-27
 

docs/index.md

@@ -42,6 +42,13 @@ Use [composer](https://getcomposer.org) to install PhpSpreadsheet into your proj
 composer require phpoffice/phpspreadsheet
 ```
 
+Or also download the documentation and samples if you plan to use them:
+
+```sh
+composer require phpoffice/phpspreadsheet --prefer-source
+```
+
+
 ## Hello World
 
 This would be the simplest way to write a spreadsheet:
@@ -64,8 +71,8 @@ $writer->save('hello world.xlsx');
 
 ## Learn by example
 
-A good way to get started is to run some of the samples. Serve the samples via
-PHP built-in webserver:
+A good way to get started is to run some of the samples. Don't forget to download them via `--prefer-source` composer
+flag. And then serve them via PHP built-in webserver:
 
 ```sh
 php -S localhost:8000 -t vendor/phpoffice/phpspreadsheet/samples