Fix a few deserialization bugs. These used to work, so I think perhaps geckodriver changed their responses.
Fix a few deserialization bugs. These used to work, so I think perhaps geckodriver changed their responses.

# Conflicts:
#	src/lib.rs

fluffysquirrels/webdriver_client_rust,fluffysquirrels/webdriver_client_rust,fluffysquirrels/webdriver_client_rust