Fix(no_std): boxed not in collections

[kamarkiewicz]

This fixes just a basic compilation without std feature on current nightly channel. More work has to be done to adjust parsers to no_std.

[coveralls]

Coverage increased (+0.009%) to 87.962% when pulling 7a99600 on kamarkiewicz:boxed-in-alloc into 56d0acc on Geal:master.

[coveralls]

Coverage increased (+0.009%) to 87.962% when pulling 7a99600 on kamarkiewicz:boxed-in-alloc into 56d0acc on Geal:master.

[coveralls]

Coverage increased (+0.009%) to 87.962% when pulling 7a99600 on kamarkiewicz:boxed-in-alloc into 56d0acc on Geal:master.

[coveralls]

Coverage increased (+0.009%) to 87.962% when pulling 6fc2f34 on kamarkiewicz:boxed-in-alloc into 56d0acc on Geal:master.

[coveralls]

Coverage increased (+0.009%) to 87.962% when pulling 6fc2f34 on kamarkiewicz:boxed-in-alloc into 56d0acc on Geal:master.

[coveralls]

Coverage increased (+0.009%) to 87.962% when pulling 6fc2f34 on kamarkiewicz:boxed-in-alloc into 56d0acc on Geal:master.

[Geal]

when was boxed moved out?

[kamarkiewicz]

Please take a look here. Last working nightly version where build command is cargo build --no-default-features is rustc 1.19.0-nightly (554c685b0 2017-06-14)

[kamarkiewicz]

Relevant issues in rust compiler are rust-lang/rust#27700 and rust-lang/rust#27783

[Geal]

merged in the "result" branch for nom 4.0