Linux support. (#3)

* Compiling and running on Linux.

* Fix xpointer constructor.

* Convert dependencies to submodules.

* Fix wchar_t usage for Linux.

thirdparty/CMakeLists.txt

@@ -0,0 +1,13 @@
+add_subdirectory(${THIRDPARTY_ROOT}/disasm)
+
+if (NOT TARGET fmt::fmt)
+    add_subdirectory(${THIRDPARTY_ROOT}/fmt)
+endif()
+
+if (NOT TARGET tomlplusplus::tomlplusplus)
+    add_subdirectory(${THIRDPARTY_ROOT}/tomlplusplus)
+endif()
+
+if (NOT TARGET xxHash::xxhash)
+    add_subdirectory(${THIRDPARTY_ROOT}/xxHash/cmake_unofficial)
+endif()