Merge branch '1.6' into 2.0

* 1.6:
  Update PR template
  Generate changelog for v1.6.0
  Add note about Sylius 1.14 in the UPGRADE file
  Improve installation guide
  Fix installation guide routes importing step

.github/PULL_REQUEST_TEMPLATE.md

@@ -1,6 +1,6 @@
 | Q               | A
 | --------------- | -----
-| Branch?         | 1.4 (security fixes), 1.5 (bug fixes, improvements), 1.6 (new features)
+| Branch?         | 1.5 (security fixes), 1.6 (bug fixes, improvements), 2.0 (new features)
 | Bug fix?        | no/yes
 | New feature?    | no/yes
 | Related tickets | fixes #X, partially #Y, mentioned in #Z

README.md

@@ -37,6 +37,12 @@ From Administrator's point of view, every Refund request results in creating two
 
 ## Installation
 
+#### Beware!
+
+This installation instruction assumes that you're using Symfony Flex. If you don't, take a look at the
+[legacy installation instruction](docs/legacy_installation.md). However, we strongly encourage you to use
+Symfony Flex, it's much quicker!
+
 1. Require plugin with composer:
 
     ```bash
@@ -70,12 +76,6 @@ From Administrator's point of view, every Refund request results in creating two
    WKHTMLTOPDF_PATH=/usr/local/bin/wkhtmltopdf # Change this! :)
    ```
 
-#### Beware!
-
-This installation instruction assumes that you're using Symfony Flex. If you don't, take a look at the
-[legacy installation instruction](docs/legacy_installation.md). However, we strongly encourage you to use
-Symfony Flex, it's much quicker! :)
-
 ## Extension points
 
 Refund Plugin is strongly based on both commands and events. Let's take RefundUnitsAction as an example. The whole

docs/legacy_installation.md

@@ -1,4 +1,4 @@
-### Legacy installation (without SymfonyFlex)
+### Legacy installation (without Symfony Flex)
 
 1. Require plugin with composer: