Rename Encryption-Key to Crypto-Key, "key" parameter to "aesgcm128".

Rename Encryption-Key to Crypto-Key, "key" parameter to "aesgcm128".

Mechanical renames to align us with draft-thomson-http-encryption-02.
Beyond -02, this CL also integrates the rename from the Encryption-Key
header to Crypto-Key[1], and the "key" parameter to "aesgcm128"[2].

Note that the algorithmic changes of [1] have not been implemented yet.

[1] https://goo.gl/f9ktM0
[2] https://goo.gl/hX9g3C

BUG=486040
Committed: https://crrev.com/471cd60ba3695e430ca3bb42baabe35485a84834
Cr-Commit-Position: refs/heads/master@{#359840}

[Peter Beverloo, 2015-11-16 11:46:29]

peter@chromium.org changed reviewers:
+ mvanouwerkerk@chromium.org

[Michael van Ouwerkerk, 2015-11-16 11:58:24]

lgtm

[Peter Beverloo, 2015-11-16 14:30:21]

The CQ bit was checked by peter@chromium.org

[Peter Beverloo, 2015-11-16 14:30:21]

The patchset sent to the CQ was uploaded after l-g-t-m from
mvanouwerkerk@chromium.org
Link to the patchset: https://codereview.chromium.org/1446163002/#ps20001
(title: "one more rename")

[commit-bot: I haz the power, 2015-11-16 14:30:42]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1446163002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1446163002/20001

[commit-bot: I haz the power, 2015-11-16 15:21:45]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-11-16 15:22:44]

Patchset 2 (id:??) landed as
https://crrev.com/471cd60ba3695e430ca3bb42baabe35485a84834
Cr-Commit-Position: refs/heads/master@{#359840}