Enforce variable init

There were a few places we weren't initting our variables per cpp core
guidelines.  Fix all of them, and enable checks for this.

Signed-off-by: Ed Tanous <edtanous@google.com>
Change-Id: Iba09924beb9fb26f597ff94d1cecbd6d6b1af912
diff --git a/include/multipart_parser.hpp b/include/multipart_parser.hpp
index e385558..ee028f1 100644
--- a/include/multipart_parser.hpp
+++ b/include/multipart_parser.hpp
@@ -337,10 +337,10 @@
     static constexpr char hyphen = '-';
     static constexpr char colon = ':';
 
-    std::array<bool, 256> boundaryIndex;
+    std::array<bool, 256> boundaryIndex{};
     std::string lookbehind;
-    State state;
-    Boundary flags;
+    State state{State::START};
+    Boundary flags{Boundary::NON_BOUNDARY};
     size_t index = 0;
     size_t partDataMark = 0;
     size_t headerFieldMark = 0;