Add timeout kwarg to 'from_warehouse'

[wbwakeman]

Increase default timeout value:

AllenSDK/allensdk/brain_observatory/ecephys/ecephys_project_api/http_engine.py

Line 14 in 924757e

DEFAULT_TIMEOUT = 10 * 60 # seconds

Add 'timeout' as a kwarg to the from_warehouse convenience

AllenSDK/allensdk/brain_observatory/ecephys/ecephys_project_cache.py

Line 586 in 924757e

def from_warehouse(cls,