Refactoring louloulibs and cmake

Use OBJECT libraries
Remove the louloulibs directory
Write FOUND variables in the cache

src/utils/sha1.cpp

@@ -0,0 +1,32 @@
+#include <utils/sha1.hpp>
+
+#include <biboumi.h>
+
+#ifdef BOTAN_FOUND
+# include <botan/hash.h>
+# include <botan/hex.h>
+#endif
+#ifdef GCRYPT_FOUND
+# include <gcrypt.h>
+# include <vector>
+# include <iomanip>
+# include <sstream>
+#endif
+
+std::string sha1(const std::string& input)
+{
+#ifdef BOTAN_FOUND
+  auto sha1 = Botan::HashFunction::create_or_throw("SHA-1");
+  sha1->update(input);
+  return Botan::hex_encode(sha1->final(), false);
+#endif
+#ifdef GCRYPT_FOUND
+  const auto hash_length = gcry_md_get_algo_dlen(GCRY_MD_SHA1);
+  std::vector<uint8_t> output(hash_length, {});
+  gcry_md_hash_buffer(GCRY_MD_SHA1, output.data(), input.data(), input.size());
+  std::ostringstream digest;
+  for (std::size_t i = 0; i < hash_length; i++)
+    digest << std::hex << std::setfill('0') << std::setw(2) << static_cast<int>(output[i]);
+  return digest.str();
+#endif
+}