Implement mode/owner and string conversions

Move Manager::convertToMode() to utils::strToMode();
Move Manager::convertToOwner() to utils::strToOwner();
Add utils::modeToStr() and utils::ownerToStr();
Adjust and add unit tests.

Change-Id: Ied35d0e732c477017e1b2db1a3464b0425b12387
Signed-off-by: Lei YU <mine260309@gmail.com>
diff --git a/test/Makefile.am b/test/Makefile.am
index b8ea41c..3071c72 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -9,7 +9,8 @@
     TestEpochBase.cpp \
     TestBmcEpoch.cpp \
     TestHostEpoch.cpp \
-	TestManager.cpp
+    TestManager.cpp \
+    TestUtils.cpp
 
 test_LDADD = $(top_builddir)/libtimemanager.la