fixed header checking
fixed header checking

its a bitmask, not a length

nusepo/SiK,tridge/SiK,LorenzMeier/SiK,weera00/SiK,weera00/SiK,mikeclement/SiK,davidbuzz/SiK,RFDesign/SiK,nusepo/SiK,tridge/DavisSi1000,geeksville/SiK,geeksville/SiK,RFDesign/SiK,tomszilagyi/SiK,LorenzMeier/SiK,tomszilagyi/SiK,RFDesign/SiK,joeman155/SiK,weera00/SiK,Serveurperso/SiK,RFDesign/SiK,tridge/DavisSi1000,mikeclement/SiK,Serveurperso/SiK,geeksville/SiK,phelpsw/SiK,tomszilagyi/SiK,GaloisInc/smaccmpilot-SiK,joeman155/SiK,jschall/SiK,mikeclement/SiK,jschall/SiK,phelpsw/SiK,GaloisInc/smaccmpilot-SiK,RFDesign/SiK,tridge/SiK,phelpsw/SiK,Dronecode/SiK,joeman155/SiK,jschall/SiK,tridge/SiK,mikeclement/SiK,davidbuzz/SiK,davidbuzz/SiK,gardners/SiK,tomszilagyi/SiK,tridge/DavisSi1000,joeman155/SiK,weera00/SiK,Dronecode/SiK,phelpsw/SiK,geeksville/SiK,davidbuzz/SiK,Serveurperso/SiK,gardners/SiK,Serveurperso/SiK,tridge/SiK,chrissnell/DavisSi1000,geeksville/SiK,GaloisInc/smaccmpilot-SiK,nusepo/SiK,phelpsw/SiK,gardners/SiK,weera00/SiK,chrissnell/DavisSi1000,tridge/SiK,joeman155/SiK,mikeclement/SiK,tomszilagyi/SiK,gardners/SiK,Dronecode/SiK,LorenzMeier/SiK,chrissnell/DavisSi1000,Dronecode/SiK,tridge/DavisSi1000,nusepo/SiK,jschall/SiK,davidbuzz/SiK,chrissnell/DavisSi1000,LorenzMeier/SiK,chrissnell/DavisSi1000,GaloisInc/smaccmpilot-SiK,nusepo/SiK