fix: use proj.device instead of hardcoded cuda, fix README typos

- Replace hardcoded device="cuda" with proj.device in SIGReg for
  portability (e.g. macOS MPS, CPU)
- Fix "Both functions accept" → "This function accepts" (only one
  function is shown)
- Fix "please reference in your paper" → "please reference it in
  your paper"

module.py

@@ -27,7 +27,7 @@ class SIGReg(torch.nn.Module):
         proj: (T, B, D)
         """
         # sample random projections
-        A = torch.randn(proj.size(-1), self.num_proj, device="cuda")
+        A = torch.randn(proj.size(-1), self.num_proj, device=proj.device)
         A = A.div_(A.norm(p=2, dim=0))
         # compute the epps-pulley statistic
         x_t = (proj @ A).unsqueeze(-1) * self.t