[py] add headless convenience method for Firefox Options
[py] add headless convenience method for Firefox Options

lmtierney/selenium,juangj/selenium,Tom-Trumper/selenium,titusfortner/selenium,mach6/selenium,5hawnknight/selenium,joshbruning/selenium,GorK-ChO/selenium,chrisblock/selenium,krmahadevan/selenium,krmahadevan/selenium,oddui/selenium,jsakamoto/selenium,joshbruning/selenium,joshmgrant/selenium,SeleniumHQ/selenium,asolntsev/selenium,jabbrwcky/selenium,markodolancic/selenium,Tom-Trumper/selenium,davehunt/selenium,markodolancic/selenium,davehunt/selenium,titusfortner/selenium,joshmgrant/selenium,5hawnknight/selenium,asolntsev/selenium,titusfortner/selenium,krmahadevan/selenium,markodolancic/selenium,Ardesco/selenium,juangj/selenium,jabbrwcky/selenium,Ardesco/selenium,Dude-X/selenium,asolntsev/selenium,SeleniumHQ/selenium,joshbruning/selenium,SeleniumHQ/selenium,jabbrwcky/selenium,asolntsev/selenium,davehunt/selenium,valfirst/selenium,Tom-Trumper/selenium,HtmlUnit/selenium,jsakamoto/selenium,asashour/selenium,joshbruning/selenium,GorK-ChO/selenium,jsakamoto/selenium,chrisblock/selenium,asolntsev/selenium,SeleniumHQ/selenium,twalpole/selenium,HtmlUnit/selenium,lmtierney/selenium,Dude-X/selenium,oddui/selenium,chrisblock/selenium,jabbrwcky/selenium,krmahadevan/selenium,titusfortner/selenium,chrisblock/selenium,valfirst/selenium,asolntsev/selenium,Ardesco/selenium,Tom-Trumper/selenium,Dude-X/selenium,Ardesco/selenium,joshmgrant/selenium,joshmgrant/selenium,titusfortner/selenium,markodolancic/selenium,chrisblock/selenium,5hawnknight/selenium,davehunt/selenium,valfirst/selenium,HtmlUnit/selenium,jabbrwcky/selenium,5hawnknight/selenium,twalpole/selenium,mach6/selenium,joshbruning/selenium,titusfortner/selenium,joshmgrant/selenium,jsakamoto/selenium,davehunt/selenium,joshbruning/selenium,HtmlUnit/selenium,asolntsev/selenium,twalpole/selenium,5hawnknight/selenium,chrisblock/selenium,valfirst/selenium,valfirst/selenium,davehunt/selenium,Dude-X/selenium,markodolancic/selenium,GorK-ChO/selenium,asashour/selenium,oddui/selenium,juangj/selenium,mach6/selenium,juangj/selenium,lmtierney/selenium,asashour/selenium,juangj/selenium,Tom-Trumper/selenium,titusfortner/selenium,oddui/selenium,valfirst/selenium,GorK-ChO/selenium,GorK-ChO/selenium,Ardesco/selenium,davehunt/selenium,markodolancic/selenium,krmahadevan/selenium,HtmlUnit/selenium,asolntsev/selenium,jsakamoto/selenium,Ardesco/selenium,jabbrwcky/selenium,jabbrwcky/selenium,jabbrwcky/selenium,lmtierney/selenium,mach6/selenium,Dude-X/selenium,chrisblock/selenium,joshmgrant/selenium,lmtierney/selenium,oddui/selenium,Dude-X/selenium,markodolancic/selenium,twalpole/selenium,twalpole/selenium,mach6/selenium,mach6/selenium,SeleniumHQ/selenium,Dude-X/selenium,mach6/selenium,chrisblock/selenium,joshmgrant/selenium,markodolancic/selenium,5hawnknight/selenium,krmahadevan/selenium,joshmgrant/selenium,Ardesco/selenium,twalpole/selenium,joshbruning/selenium,valfirst/selenium,juangj/selenium,HtmlUnit/selenium,Tom-Trumper/selenium,twalpole/selenium,titusfortner/selenium,titusfortner/selenium,SeleniumHQ/selenium,oddui/selenium,SeleniumHQ/selenium,valfirst/selenium,joshmgrant/selenium,lmtierney/selenium,twalpole/selenium,asashour/selenium,lmtierney/selenium,GorK-ChO/selenium,SeleniumHQ/selenium,krmahadevan/selenium,asashour/selenium,juangj/selenium,HtmlUnit/selenium,jsakamoto/selenium,SeleniumHQ/selenium,markodolancic/selenium,jsakamoto/selenium,titusfortner/selenium,5hawnknight/selenium,jabbrwcky/selenium,valfirst/selenium,joshmgrant/selenium,Ardesco/selenium,titusfortner/selenium,5hawnknight/selenium,chrisblock/selenium,davehunt/selenium,asashour/selenium,jsakamoto/selenium,5hawnknight/selenium,juangj/selenium,twalpole/selenium,jsakamoto/selenium,valfirst/selenium,krmahadevan/selenium,Tom-Trumper/selenium,GorK-ChO/selenium,oddui/selenium,joshbruning/selenium,SeleniumHQ/selenium,Dude-X/selenium,asashour/selenium,oddui/selenium,SeleniumHQ/selenium,Dude-X/selenium,HtmlUnit/selenium,lmtierney/selenium,HtmlUnit/selenium,asashour/selenium,mach6/selenium,asashour/selenium,mach6/selenium,GorK-ChO/selenium,lmtierney/selenium,joshbruning/selenium,asolntsev/selenium,Tom-Trumper/selenium,oddui/selenium,Ardesco/selenium,HtmlUnit/selenium,juangj/selenium,GorK-ChO/selenium,Tom-Trumper/selenium,valfirst/selenium,krmahadevan/selenium,davehunt/selenium,joshmgrant/selenium