wip: Wrap the cuda context

Open question: leverage deref and drop to make push and pop more
idiomatic.

src/cuda/context.rs

@@ -0,0 +1,45 @@
+use ffi::cuda::*;
+
+use cuda::device::CuDevice;
+
+pub struct CuContext {
+    context : CUcontext,
+}
+
+impl CuContext {
+    pub fn new(dev : CuDevice, flags : u32) -> Result<CuContext, CUresult> {
+        let mut ctx = CuContext { context : 0 };
+        let res = unsafe { cuCtxCreate(&mut ctx.context as *mut CUcontext, dev.device) }
+
+        wrap!(ctx, res)
+    }
+
+    pub fn get_api_version(&self) -> Result<u32, CUresult> {
+        let mut ver = 0;
+        let res = unsafe { cuGetApiVersion(self.context, &mut ver as *mut u32)};
+
+        wrap!(ver, res)
+    }
+
+    pub fn pop() -> Result<, CUresult> {
+        let res = unsafe { cuCtxPopCurrent
+    }
+}
+
+/* TODO: leverage clone/drop/deref traits
+impl Clone for CuContext {
+
+}
+
+impl Deref for CuContext {
+
+}
+*/
+
+impl Drop for CuContext {
+    fn drop(&mut self) {
+        unsafe {
+            cuCtxDestroy(self.context);
+        }
+    }
+}