Eliminate the C FFI; Namespace lib API and DeviceManager

We decided to get rid of the C FFI for libs. It was becoming too intricate
and complicated. It was becoming a technical burden and expanding into
too much extra code. It's unfortunate, but we'll have to give up on getting
out-of-tree hot-loadable libraries the easy way.

It's possible to still do it with cross compilation or by keeping track
of the libstdc++ version that the running harikoff binary was compiled
against. Then we can ensure that our loadable lib code is linked against
that same libstdc++ code and this should ensure ABI stability.

hcore/include/senseApis/senseApiManager.h

@@ -38,8 +38,8 @@ public:
     void finalizeAllSenseApiLibs(void);
 
     void attachAllSenseDevicesFromSpecs(void);
-    void attachSenseDevice(const SenseDeviceSpec& spec);
-    void detachSenseDevice(const SenseDeviceSpec& spec);
+    void attachSenseDevice(const device::SenseDeviceSpec& spec);
+    void detachSenseDevice(const device::SenseDeviceSpec& spec);
     void detachAllSenseDevices(void);
 
     std::string stringifyLibs() const;