Extended the settings activity
Changing the values does not change anything yet :D To be continued...

Reading threshold from preferences. First draft of SliderPreference.
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#	new file:   CircleToUnlock.iml
#	modified:   Implementierung/CircleToUnlock/CircleToUnlock.iml
#	modified:   Implementierung/CircleToUnlock/build.gradle
#	modified:   Implementierung/CircleToUnlock/src/main/AndroidManifest.xml
#	modified:   Implementierung/CircleToUnlock/src/main/java/de/uniulm/circletounlock/Controller/PasswordValidation.java
#	modified:   Implementierung/CircleToUnlock/src/main/java/de/uniulm/circletounlock/MainActivity.java
#	new file:   Implementierung/CircleToUnlock/src/main/java/de/uniulm/circletounlock/SettingsActivity.java
#	modified:   Implementierung/CircleToUnlock/src/main/java/de/uniulm/circletounlock/View/Grid.java
#	modified:   Implementierung/CircleToUnlock/src/main/res/layout/activity_main.xml
#	modified:   Implementierung/CircleToUnlock/src/main/res/values/strings.xml
#	new file:   Implementierung/CircleToUnlock/src/main/res/values/strings_activity_settings.xml
#	new file:   Implementierung/CircleToUnlock/src/main/res/xml/pref_general.xml
#	modified:   Implementierung/Implementierung.iml
#	modified:   Implementierung/local.properties
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#	modified:   CircleToUnlock.iml
#	modified:   Implementierung/.gradle/1.9/taskArtifacts/cache.properties.lock
#	modified:   Implementierung/.gradle/1.9/taskArtifacts/fileHashes.bin
#	modified:   Implementierung/.gradle/1.9/taskArtifacts/fileSnapshots.bin
#	modified:   Implementierung/.gradle/1.9/taskArtifacts/outputFileStates.bin
#	modified:   Implementierung/.gradle/1.9/taskArtifacts/taskArtifacts.bin
#	modified:   Implementierung/.idea/gradle.xml
#	modified:   Implementierung/.idea/misc.xml
#	modified:   Implementierung/.idea/vcs.xml
#	modified:   Implementierung/.idea/workspace.xml
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#	local.properties