no log.Fatal, new interface for ComputeSecret

no log.Fatal any more
new Check for Curve25519
return error for ComputeSecret

not compatible with previous version

Delete Unused Point Struct

Delete Point struct

Signed-off-by: huraway <[email protected]>

Migrate to new X25519 API

Everything about type check and crypto.PrivateKey|crypto.Publickey removed

return []byte when use generic.go interface

v0.3.0

fix generic.go with left problems