left navbar icon hitSlop feature

[zeritte]

We should be able to increase touchable area of left navbar icon.
When using navbar component of galio, user has to click exactly on top of go back or open drawer icon. however; this really reduces the user experience.
this is related to galio-org/galio#94

Being able to add hit slop to left navbar icon
With the help of a few lines of code; users of galio may add hitSlop to left navbar icon. example code is given below.

What about right icon?
Since right can be rendered in a whole component, I don't think we need to specify rightHitSlop.

example code:

renderRight = () => {
    const { white, title, navigation } = this.props;
    const { routeName } = navigation.state;

    if (title === "Title") {
      return [
        //some things
      ];
    }
}
<NavBar
   back={back}
   title={title}
   style={styles.navbar}
   transparent={transparent}
   right={this.renderRight()}
   leftHitSlop={{ top: 30, bottom: 30, left: 30, right: 30 }} // important part!!!
   leftStyle={{ paddingVertical: -12, flex: 0.3 }}
   leftIconColor={white ? theme.COLORS.WHITE : theme.COLORS.ICON}
   titleStyle={[
      styles.title,
      { color: theme.COLORS[white ? "WHITE" : "ICON"] }
          ]}
   onLeftPress={this.handleLeftPress}
/>