Add Apache notice to all source file headers

[johnluther]

Don't need to put this in the TVML files, just code. Here is the text:

/**
* Copyright 2015 Longtail Ad Solutions Inc.
*
* 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.
**/

[johnluther]

LGTM