Auto merge of #378 - ignatenkobrain:license, r=SimonSapin

add licenses to sub-crates (Closes #376)

Signed-off-by: Igor Gnatenko <ignatenko@redhat.com>

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idna/LICENSE-APACHE

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+../LICENSE-APACHE

idna/LICENSE-MIT

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+../LICENSE-MIT

percent_encoding/LICENSE-APACHE

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+../LICENSE-APACHE

percent_encoding/LICENSE-MIT

@@ -0,0 +1 @@
+../LICENSE-MIT

url_serde/LICENSE-APACHE

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+../LICENSE-APACHE

url_serde/LICENSE-MIT

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+../LICENSE-MIT