appveyor: clean-up install; move 'prepare' to 'build_script'

fixes #38

appveyor/.appveyor.yml.example-full

@@ -12,14 +12,6 @@
 cache:
   - C:\Users\appveyor\.tools
 
-#---------------------------------#
-#       additional packages       #
-#---------------------------------#
-
-install:
-# for the sequencer
-  - cinst re2c
-
 #---------------------------------#
 #       repository cloning        #
 #---------------------------------#
@@ -43,6 +35,16 @@ skip_commits:
     - '**/*.md'
     - '.travis.yml'
 
+#---------------------------------#
+#       additional packages       #
+#---------------------------------#
+
+install:
+# fetch submodules (like ci-scripts)
+  - cmd: git submodule update --init --recursive
+# for the sequencer
+  - cinst re2c
+
 #---------------------------------#
 #   build matrix configuration    #
 #---------------------------------#
@@ -113,11 +115,8 @@ matrix:
 #     building & testing          #
 #---------------------------------#
 
-install:
-  - cmd: git submodule update --init --recursive
-  - cmd: python .ci/appveyor/do.py prepare
-
 build_script:
+  - cmd: python .ci/appveyor/do.py prepare
   - cmd: python .ci/appveyor/do.py build
 
 test_script:

appveyor/.appveyor.yml.example-mini

@@ -19,6 +19,9 @@ skip_commits:
     - '**/*.md'
     - '.travis.yml'
 
+install:
+  - cmd: git submodule update --init --recursive
+
 image: Visual Studio 2019
 
 # Build Configurations: dll/static, regular/debug
@@ -54,11 +57,8 @@ matrix:
   - platform: x64
     CMP: vs2008
 
-install:
-  - cmd: git submodule update --init --recursive
-  - cmd: python .ci/appveyor/do.py prepare
-
 build_script:
+  - cmd: python .ci/appveyor/do.py prepare
   - cmd: python .ci/appveyor/do.py build
 
 test_script: