Usage of composer.phar if it's found

scripts/install.sh

@@ -2,6 +2,8 @@
 # You can execute this file to install wallabag
 # eg: `sh install.sh prod`
 
+COMPOSER_COMMAND='composer'
+
 DIR="${BASH_SOURCE%/*}"
 if [[ ! -d "$DIR" ]]; then DIR="$PWD"; fi
 . "$DIR/require.sh"
@@ -10,5 +12,5 @@ ENV=$1
 TAG=$(git describe --tags $(git rev-list --tags --max-count=1))
 
 git checkout $TAG
-SYMFONY_ENV=$ENV composer install --no-dev -o --prefer-dist
+SYMFONY_ENV=$ENV $COMPOSER_COMMAND install --no-dev -o --prefer-dist
 php bin/console wallabag:install --env=$ENV