fix(time): The time crate has moved to out-of-tree.

This adds a dependency on the time crate found in rust-lang/time
and fixes a field rename from tm_gmtoff to tm_utcoff.

add time dependency

tm_gmtoff has been renamed to tm_utcoff
Merge branch 'jgillich-time'
Fix client example so it compiles

`URL::parse()` needs an `unwrap()`, the `let res = ...` needs a semicolon, and I changed the example to set a real header.
Merge pull request #121 from jkleint/patch-1

Fix client example so it compiles
std::from_str has been moved to std::str
TaskPool updates
Merge pull request #122 from jgillich/str

from_str & TaskPool updates
make Headers implement Clone
spelling error in readme
Merge pull request #124 from austinpray/patch-1

spelling error in readme
move other header parse utils to util module
Now using use along with enums, as per https://github.com/rust-lang/rust/pull/18973.
refactor(status): replace glob with namespaced variants
fix(http): is_valid_method expects &-ptr
Merge pull request #127 from jgillich/enum

namespaced enums
(fix) Replace find_equiv with a lifetime transmute.
(fix) Fix benchmarks for rust API changes.
Merge pull request #128 from reem/find-equiv

Rust update
fix(readme): make the server example compile.
refactor(response): made deconstruct available on all response types.