DATACOUCH-170 - Fix N1QL annotation and inline querying in docs

In some places in the doc (javadoc, README, asciidoc), the annotation was still referred to as N1QL instead of Query...

Improved doc on inline statement for N1QL queries allowing the use of positional `$1` placeholders.

src/main/java/org/springframework/data/couchbase/repository/query/StringN1qlBasedQuery.java

@@ -26,6 +26,10 @@ import org.springframework.data.repository.query.RepositoryQuery;
 
 /**
  * A {@link RepositoryQuery} for Couchbase, based on N1QL and a String statement.
+ * <p/>
+ * The statement can contain positional placeholders (eg. <code>name = $1</code>) that will map to the
+ * method's parameters, in the same order.
+ * <p/>
  * The statement can contain placeholders for the {@link #PLACEHOLDER_BUCKET bucket namespace},
  * the {@link #PLACEHOLDER_ENTITY ID and CAS fields} necessary for entity reconstruction or
  * a shortcut that covers {@link #PLACEHOLDER_SELECT_FROM SELECT AND FROM clauses}.