Auto merge of #73 - NatalyaKovalova:ios-support, r=jdm

Add iOS support

Ability to build core-text-rs for iOS platform have been added in this PR.
For building could be used:
cargo build --target aarch64-apple-ios

@larsbergstrom

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Cargo.toml

@@ -15,7 +15,5 @@ mountainlion = []
 [dependencies]
 foreign-types = "0.3"
 libc = "0.2"
-
-[target.x86_64-apple-darwin.dependencies]
 core-foundation = "0.4"
 core-graphics = "0.11"

src/font.rs

@@ -417,7 +417,7 @@ pub fn cascade_list_for_languages(font: &CTFont, language_pref_list: &CFArray) -
     }
 }
 
-#[link(name = "ApplicationServices", kind = "framework")]
+#[link(name = "CoreText", kind = "framework")]
 extern {
     /*
      * CTFont.h