Initial commit
Add license information to project

The project's source code is licensed under the Apache
License version 2.0.
Add basic build definition

The build is done using SBT. The projct uses version 0.12.3 and Scala
2.10.1.
Add IDEA specific files to gitignore
Add Sigmoid activation funtion
Update SBT and Scala

Use the latest versions of Scala and SBT.
Add basic feed forward neural network

It is currently only an implementation, that handles the layers of a
neuronal network. The calculation itself is not implemented yet.