src: moved Java indexer from JavaSymbolSolver to Eclipse JDT

* added some more tests
* changed 3rd party licenses respectively

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java_indexer/src/main/java/com/sourcetrail/Range.java

@@ -0,0 +1,27 @@
+package com.sourcetrail;
+
+public class Range 
+{
+	public Position begin = new Position();
+	public Position end = new Position();
+	
+	public Range() 
+	{
+	}
+	
+	public Range(int beginLine, int beginColumn, int endLine, int endColumn) 
+	{
+		this.begin.line = beginLine;
+		this.begin.column = beginColumn;
+		this.end.line = endLine;
+		this.end.column = endColumn;
+	}
+	
+	public Range(Position begin, Position end) 
+	{
+		this.begin.line = begin.line;
+		this.begin.column = begin.column;
+		this.end.line = end.line;
+		this.end.column = end.column;
+	}
+}