Fix commons-io signatures that fail in commons-io v2.7 (#169)

Commons-IO signatures fails to resolve in commons-io v2.7, as there was an incompatible change; This also adds signatures for version 2.7 (a new abstract class that caused this issue).

In a later version of forbiddenapis there will be a more robust fix for this (resolving virtual methods during signatures parsing)

Author: uschindler

src/main/resources/de/thetaphi/forbiddenapis/signatures/commons-io-unsafe-1.0.txt

@@ -23,4 +23,6 @@ org.apache.commons.io.IOUtils#toByteArray(java.io.Reader)
 org.apache.commons.io.IOUtils#toByteArray(java.lang.String)
 org.apache.commons.io.IOUtils#toString(byte[])
 org.apache.commons.io.IOUtils#toString(java.io.InputStream)
+
+@ignoreUnresolvable
 org.apache.commons.io.output.ByteArrayOutputStream#toString()

src/main/resources/de/thetaphi/forbiddenapis/signatures/commons-io-unsafe-2.7.txt

@@ -0,0 +1,20 @@
+# (C) Copyright Uwe Schindler (Generics Policeman) and others.
+# Parts of this work are licensed to the Apache Software Foundation (ASF)
+# under one or more contributor license agreements.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+@includeBundled commons-io-unsafe-2.6
+
+@defaultMessage Uses default charset
+org.apache.commons.io.output.AbstractByteArrayOutputStream#toString()