Use guarded memory for the box_easy2() test + non-deterministic buffer sizes
Use guarded memory for the box_easy2() test
+ non-deterministic buffer sizes

eburkitt/libsodium,Payshares/libsodium,rustyhorde/libsodium,Payshares/libsodium,rustyhorde/libsodium,eburkitt/libsodium,Payshares/libsodium,pmienk/libsodium,rustyhorde/libsodium,pmienk/libsodium,rustyhorde/libsodium,eburkitt/libsodium,pmienk/libsodium