Auto merge of #351 - behnam:ucd10, r=SimonSapin

[idna] Update data to Unicode 10.0 and fix logic

* Change the behavior of ToASCII step to match the spec and prevent failures on some cases when a domain name starts with leading dots (FULL STOPs), as requested in #166. (Another attempt on #337 and #171)

* Update `IdnaTest.txt` file to UCD 10.0 and fix Validation Rules, specially Bidi Rules, for the tests to pass.

* Add TODO marks for new flags introduced in Unicode 10.0 version of UTS#46. (http://www.unicode.org/reports/tr46/proposed.html)

* Add integration test for `rust-url` crate for the new behavior.

Fix #166

<!-- Reviewable:start -->
---
This change is [<img src="https://reviewable.io/review_button.svg" height="34" align="absmiddle" alt="Reviewable"/>](https://reviewable.io/reviews/servo/rust-url/351)
<!-- Reviewable:end -->

Author: bors-servo

idna/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "idna"
-version = "0.1.2"
+version = "0.1.3"
 authors = ["The rust-url developers"]
 description = "IDNA (Internationalizing Domain Names in Applications) and Punycode."
 repository = "https://github.com/servo/rust-url/"
@@ -14,11 +14,14 @@ test = false
 name = "tests"
 harness = false
 
+[[test]]
+name = "unit"
+
 [dev-dependencies]
 rustc-test = "0.1"
 rustc-serialize = "0.3"
 
 [dependencies]
 unicode-bidi = "0.3"
-unicode-normalization = "0.1.3"
+unicode-normalization = "0.1.5"
 matches = "0.1"