* lowered minApiVersion to 7
* fixes to layout - dark color scheme for poi list, buttons of size
150px for each device (seems to work for now, but it's a temporary
measure)
last minute fix, small screens get 100px buttons
* rework of data classes
* more stable Hardware.canGPS
+ Log.w support
+ Introduced SessionManager interface for Activity
+ Basic preset functionality. Buttons are created according to presets
* polish layout for landscape tablet, and backport changes into phone
layout. Now the screen is divided by percentage (layout_weight) not by
absolute size