Merge pull request #62 from xtext/cd_issue61

[#61] fixed theoretical sec. issue with http downloads

pom.xml

@@ -22,19 +22,20 @@ xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xs
 		<maven.compiler.target>1.8</maven.compiler.target>
 		<tycho-version>1.4.0</tycho-version>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<xtext.version>2.17.0</xtext.version>
+		<xtext.version>2.17.1</xtext.version>
+		<tycho.disableP2Mirrors>true</tycho.disableP2Mirrors>
 	</properties>
 
 	<repositories>
 		<repository>
 			<id>eclipse</id>
 			<layout>p2</layout>
-			<url>http://download.eclipse.org/releases/2019-03/</url>
+			<url>https://download.eclipse.org/releases/2019-03/</url>
 		</repository>
 		<repository>
 			<id>Xtext Update Site</id>
 			<layout>p2</layout>
-			<url>http://download.eclipse.org/modeling/tmf/xtext/updates/releases/${xtext.version}/</url>
+			<url>https://download.eclipse.org/modeling/tmf/xtext/updates/releases/${xtext.version}/</url>
 		</repository>
 	</repositories>