support block type strings in resnet

[wyli]

Is your feature request related to a problem? Please describe.
from #4678, the resnet input args should be able to understand strings in addition to the class types, the corresponding docstrings should be revised

MONAI/monai/networks/nets/resnet.py

Lines 173 to 175 in d99857c

	def __init__(
	self,
	block: Type[Union[ResNetBlock, ResNetBottleneck]],

[Nic-Ma]

Hi @yiheng-wang-nv ,

Could you please help update the ResNet for it?

Thanks in advance.

[yiheng-wang-nv]

Hi @Nic-Ma , sure. Also for SENet.