[fix] add --all flag to android update sdk command (#522)
[fix] add --all flag to android update sdk command (#522)

I got `Error: Ignoring unknown package filter 'build-tools-26.0.1` otherwise and in result a non-functioning build
Frenzie/koreader-base,Frenzie/koreader-base,koreader/koreader-base,NiLuJe/koreader-base,NiLuJe/koreader-base,houqp/koreader-base,koreader/koreader-base,Frenzie/koreader-base,houqp/koreader-base,apletnev/koreader-base,koreader/koreader-base,apletnev/koreader-base,NiLuJe/koreader-base,apletnev/koreader-base,Frenzie/koreader-base,koreader/koreader-base,houqp/koreader-base,apletnev/koreader-base,NiLuJe/koreader-base,houqp/koreader-base