* Integrate lazycell 1.2.0 into the project

...rather than getting it from the crates.io. The problem is that latest
lazycell doesn't work with rust 1.18.0 anymore that mio supports.  This
commit only adds the origincal lazycell.rs without any modifications.
I want commits to show the changes I made to the lazycell.rs 1.2.0.

* Fix lazycell to work with rust 1.18.0

* Removed example, which wouldn't compile, because lazycell wasn't detected.
* Simply use std instead of libcore.
* Removed associated constant, which is still an experimental feature in
  rust 1.18.0.

* Fix android builds

* Delete doc examples for deprecated code