Merge branch 'release' into develop

Author: chriseth

prerelease.txt

@@ -13,4 +13,4 @@ cmake -DCMAKE_BUILD_TYPE=Release -DTESTS=0 -DSTATIC_LINKING=1 &&\
 make solc && install -s  solc/solc /usr/bin	&&\
 cd / && rm -rf solidity &&\
 apk del sed build-base git make cmake gcc g++ musl-dev curl-dev boost-dev &&\
-rm -rf /var/cache/apk/*
+rm -rf /var/cache/apk/*