fs_config: add unit tests

Add some initial unit tests.

The unit tests themselves are inlined into the tool and
can be executed by running the "test" commandlet.

Example:
$ python -m unittest test_fs_config_generator.Tests
.............
----------------------------------------------------------------------
Ran 13 tests in 0.004s

OK

Test: run the test commandlet and observe for failures.

Change-Id: I1bada385fa841fd50fa958997d440f1198e15198
Signed-off-by: William Roberts <william.c.roberts@intel.com>
diff --git a/tools/fs_config/README b/tools/fs_config/README
index c50c056..d884e32 100644
--- a/tools/fs_config/README
+++ b/tools/fs_config/README
@@ -124,3 +124,19 @@
 file like so:
   1. In your C code just #include "generated_oem_aid.h" and start using the declared identifiers.
   2. In your Makefile add this static library like so: LOCAL_STATIC_LIBRARIES := liboemaids
+
+Unit Tests:
+
+From within the fs_config directory, unit tests can be executed like so:
+$ python -m unittest test_fs_config_generator.Tests
+.............
+----------------------------------------------------------------------
+Ran 13 tests in 0.004s
+
+OK
+
+One could also use nose if they would like:
+$ nose2
+
+To add new tests, simply add a test_<xxx> method to the test class. It will automatically
+get picked up and added to the test suite.