enhance the version comparison utililty

[wyli]

Is your feature request related to a problem? Please describe.
version comparison is needed for a few cases:

• MONAI/tests/utils.py

  Lines 133 to 136 in 2085a49

  	if has_pkg_res:
  	self.version_too_new = ver(torch.__version__) >= ver(".".join(map(str, self.max_version)))
  	else:
  	self.version_too_new = get_torch_version_tuple() >= self.max_version

• MONAI/monai/utils/module.py

  Lines 276 to 279 in 2085a49

  	if has_ver:
  	PT_BEFORE_1_7 = ver(torch.__version__) < ver("1.7")
  	else:
  	PT_BEFORE_1_7 = get_torch_version_tuple() < (1, 7)

• MONAI/monai/utils/deprecated.py

  Line 55 in 2085a49

  # parse the version strings in this basic way to avoid needing the `packaging` package