added next button after after a correct answer.
added switching mode.
switch from binary to decimal or from decimal to binary.
changed button description
added strings in xml file
fixed problem with big int values
fixes small errors
>Improve User Interface

>Resolving Conflicts:
Merge remote-tracking branch 'upstream_enol/master' into walter
Conflicts:
	project.properties
	res/layout/fragment_binary.xml
	res/values-en/strings.xml
	res/values/strings.xml
	src/es/uniovi/imovil/fcrtrainer/BinaryConverter.java
	src/es/uniovi/imovil/fcrtrainer/BinaryExerciseFragment.java
	src/es/uniovi/imovil/fcrtrainer/NetworkLayerExerciseFragment.java
improvements: interface
improvements: interface
improvements
trying to pull
try to pull
try to pull
try to pull
Añadido Walter
Merge branch 'walter'