Update project structure and build process

libwallet/musig/ecmult_const.h

@@ -0,0 +1,20 @@
+/***********************************************************************
+ * Copyright (c) 2015 Andrew Poelstra                                  *
+ * Distributed under the MIT software license, see the accompanying    *
+ * file COPYING or https://www.opensource.org/licenses/mit-license.php.*
+ ***********************************************************************/
+
+#ifndef SECP256K1_ECMULT_CONST_H
+#define SECP256K1_ECMULT_CONST_H
+
+#include "scalar.h"
+#include "group.h"
+
+/**
+ * Multiply: R = q*A (in constant-time)
+ * Here `bits` should be set to the maximum bitlength of the _absolute value_ of `q`, plus
+ * one because we internally sometimes add 2 to the number during the WNAF conversion.
+ */
+static void secp256k1_ecmult_const(secp256k1_gej *r, const secp256k1_ge *a, const secp256k1_scalar *q, int bits);
+
+#endif /* SECP256K1_ECMULT_CONST_H */