Feature Set .gitattributes to ignore docs and tests folder, and some source asset files which are not needed

.gitattributes

@@ -1,4 +1,12 @@
-docs/ export-ignore
+/tests export-ignore
+/docs export-ignore
+/.tx export-ignore
+/.gitattributes export-ignore
+/.gitignore export-ignore
+/.travis.yml export-ignore
+/.scrutinizer.yml export-ignore
+/*.dist export-ignore
+/behat.yml export-ignore
 
 # Line endings
 sake text eol=lf

.travis.yml

@@ -81,7 +81,7 @@ before_script:
   - composer require silverstripe/recipe-core:1.1.x-dev silverstripe/admin:1.1.x-dev silverstripe/versioned:1.1.x-dev --no-update
   - if [[ $PHPUNIT_TEST == cms ]] || [[ $BEHAT_TEST == cms ]]; then composer require silverstripe/recipe-cms:1.1.x-dev --no-update; fi
   - if [[ $PHPCS_TEST ]]; then composer global require squizlabs/php_codesniffer:^3 --prefer-dist --no-interaction --no-progress --no-suggest -o; fi
-  - composer install --prefer-dist --no-interaction --no-progress --no-suggest --optimize-autoloader --verbose --profile
+  - composer install --prefer-source --no-interaction --no-progress --no-suggest --optimize-autoloader --verbose --profile
 
 # Log constants to CI for debugging purposes
   - php ./tests/dump_constants.php