moved all files to src folder

src/Query/MatchQuery.php

src/Query/MoreLikeThisQuery.php

src/Query/MultiMatchQuery.php

src/Query/NestedQuery.php

src/Query/PrefixQuery.php

src/Query/Query.php

src/Query/QueryStringQuery.php

src/Query/RangeQuery.php

src/Query/RegexpQuery.php

src/Query/SimpleQueryStringQuery.php

src/Query/Span/SpanFirstQuery.php

src/Query/Span/SpanMultiTermQuery.php

src/Query/Span/SpanNearQuery.php

src/Query/Span/SpanNotQuery.php

src/Query/Span/SpanOrQuery.php

src/Query/Span/SpanQueryInterface.php

src/Query/Span/SpanTermQuery.php

src/Query/TermQuery.php

src/Query/TermsQuery.php

src/Query/WildcardQuery.php