Add optional timeout parameter to getfeature for WFS 1.0.0 and 1.1.0

OWSLib's implementation of getfeature for WFS 2.0.0 takes an optional timeout parameter, which was not available for WFS 1.0.0 or 1.1.0.  With version 0.8.7, owslib.util.openURL, which OWSLib's WFS 1.0.0 and 1.1.0 implementations use for getfeature, takes an optional timeout parameter, which defaults to 30 seconds.  With this short timeout, some of my client code's longer queries were timing out for no good reason.  To solve this, added an optional timeout parameter to WebFeatureService_1_0_0.getfeature and WebFeatureService_1_1_0.getfeature, so that client code can control the timeout duration.