Fixes and cleanup to file functions and module

- unified set attribute functions ... not sure why 2 identical functions
exist with diff names, now there are 3 while i repoint all modules to 1
- fixed issue with symlinks being created w/o existing src when force=no
- refactored conditionals, simplified where possible
- added tests for symlink to nonexistant source, with both force options
- made symlink on existing attomic (force)

test/integration/roles/test_file/tasks/main.yml

@@ -164,5 +164,24 @@
     that:
       - "file11_result.uid == 1235"
 
+- name: fail to create soft link to non existant file
+  file: src=/noneexistant dest={{output_dir}}/soft2.txt state=link force=no
+  register: file12_result
+  ignore_errors: true
+
+- name: verify that link was not created
+  assert:
+    that:
+      - "file12_result.failed == true"
+
+- name: force creation soft link to non existant
+  file: src=/noneexistant dest={{output_dir}}/soft2.txt state=link force=yes
+  register: file13_result
+
+- name: verify that link was created
+  assert:
+    that:
+      - "file13_result.changed == true"
+
 - name: remote directory foobar
   file: path={{output_dir}}/foobar state=absent