Make sure composer home is always defined, remove all usage of defaults

tasks/auth_json.yml

@@ -3,5 +3,5 @@
 - name: Configure github oauth token
   template:
     src: ".composer/auth.json.j2"
-    dest: "{{ composer_home_path|default('~/.composer') }}/auth.json"
+    dest: "{{ composer_home_path }}/auth.json"
   when: composer_github_oauth != false or composer_http_basic != false

tasks/configure.yml

 ---
 
 - name: Create composer home path
-  file: path={{ composer_home_path|default('~/.composer') }} state=directory owner={{ composer_home_owner }} group={{ composer_home_group }}
+  file: path={{ composer_home_path }} state=directory owner={{ composer_home_owner }} group={{ composer_home_group }}
 
 - name: Configure composer home path
   copy: dest=/etc/profile.d/composer-home.sh mode=0755
@@ -10,11 +10,11 @@
 
 - name: Configure composer path environment
   copy: dest=/etc/profile.d/composer-path.sh mode=0755
-        content="export PATH=${PATH}:{{ composer_home_path|default('~/.composer') }}/vendor/bin\n"
+        content="export PATH=${PATH}:{{ composer_home_path }}/vendor/bin\n"
 
 - name: Global require packages
-  shell: COMPOSER_HOME={{ composer_home_path|default('~/.composer') }}
+  shell: COMPOSER_HOME={{ composer_home_path }}
          composer global require {{ item.key }}:{{ item.value }} --no-progress
-         creates={{ composer_home_path|default('~/.composer') }}/vendor/{{ item.key }}
+         creates={{ composer_home_path }}/vendor/{{ item.key }}
   with_dict: '{{ composer_global_packages }}'
   when: composer_global_packages|length > 0