Is TensorFlow a complete Machine Learning Library?
This is a big oversimplification, but there are essentially two types of machine learning libraries available today: 


Deep learning (CNN,RNN, fully connected nets, linear models)
Everything else (SVM, GBMs, Random Forests, Naive Bayes, K-NN, etc)


The reason for this is that deep learning is much more computationally intensive than other more traditional training methods, and therefore requires intense specialization of the library (e.g., using a GPU and distributed capabilities). If you're using Python and are looking for a package with the greatest breadth of algorithms, try scikit-learn. In reality, if you want to use deep learning and more traditional methods you'll need to use more than one library. There is no "complete" package.