Turn on a bunch of warnings

Turn on as many warnings as easily possible from:
https://github.com/lefticus/cppbestpractices/blob/e73393f25a85f83fed7399d8b65cb117d00b2231/02-Use_the_Tools_Available.md#L100

Tested:
ipmitool sensor list still works

Change-Id: Ied8fa66de9fcd25e448f8048c4f8216b426b6f55
Signed-off-by: James Feist <james.feist@linux.intel.com>
diff --git a/src/TachSensor.cpp b/src/TachSensor.cpp
index 45ac7ac..46f5389 100644
--- a/src/TachSensor.cpp
+++ b/src/TachSensor.cpp
@@ -142,7 +142,7 @@
                 std::getline(responseStream, response);
                 float nvalue = std::stof(response);
                 responseStream.clear();
-                if (nvalue != value)
+                if (static_cast<double>(nvalue) != value)
                 {
                     updateValue(nvalue);
                 }