Update IO library (#21)

Author: gentlegiantJGC

requirements.py

@@ -6,11 +6,11 @@
 
 PYBIND11_REQUIREMENT = "==3.0.1"
 AMULET_PYBIND11_EXTENSIONS_REQUIREMENT = "~=1.2.0.0a2"
-AMULET_IO_REQUIREMENT = "~=1.0"
+AMULET_IO_REQUIREMENT = "~=2.0.0.0a0"
 AMULET_UTILS_REQUIREMENT = "~=1.1.3.0a6"
 AMULET_ZLIB_REQUIREMENT = "~=1.0.8.0a0"
-AMULET_NBT_REQUIREMENT = "~=5.0.2.0a2"
-AMULET_CORE_REQUIREMENT = "~=2.0.7.0a0"
+AMULET_NBT_REQUIREMENT = "~=5.0.3.0a0"
+AMULET_CORE_REQUIREMENT = "~=2.0.8.0a0"
 
 if os.environ.get("AMULET_PYBIND11_EXTENSIONS_REQUIREMENT", None):
     AMULET_PYBIND11_EXTENSIONS_REQUIREMENT = f"{AMULET_PYBIND11_EXTENSIONS_REQUIREMENT},{os.environ['AMULET_PYBIND11_EXTENSIONS_REQUIREMENT']}"