Fix a bunch of warnings

using the list of warnings from here:
https://github.com/lefticus/cppbestpractices/blob/e73393f25a85f83fed7399d8b65cb117d00b2231/02-Use_the_Tools_Available.md#L100

Seems like a good place to start, and would improve things a bit
type-wise.  This patchset attempts to correct all the issues in one
shot.

Tested:
It builds.  Will test various subsystems that have been touched

Signed-off-by: Ed Tanous <ed.tanous@intel.com>
Change-Id: I588c26440e5a97f718a0f0ea74cc84107d53aa1e
diff --git a/include/dbus_monitor.hpp b/include/dbus_monitor.hpp
index 1b82697..8c46cf4 100644
--- a/include/dbus_monitor.hpp
+++ b/include/dbus_monitor.hpp
@@ -109,7 +109,7 @@
 
     connection->sendText(j.dump());
     return 0;
-};
+}
 
 template <typename... Middlewares> void requestRoutes(Crow<Middlewares...>& app)
 {
@@ -150,7 +150,7 @@
             nlohmann::json::iterator paths = j.find("paths");
             if (paths != j.end())
             {
-                int interfaceCount = thisSession.interfaces.size();
+                size_t interfaceCount = thisSession.interfaces.size();
                 if (interfaceCount == 0)
                 {
                     interfaceCount = 1;
@@ -160,7 +160,7 @@
                 // PropertiesChanged
                 thisSession.matches.reserve(thisSession.matches.size() +
                                             paths->size() *
-                                                (1 + interfaceCount));
+                                                (1U + interfaceCount));
             }
             std::string object_manager_match_string;
             std::string properties_match_string;