change theme in AndroidManifest.xml
prepare layouts for main screen in landscape and portrait modes
add file zoologo.jpg
add empty layouts aboutzoo.xml, options.xml, sightseeing.xml
add files layout-land/main.xml, res/values/styles.xml
fix code in layouts, styles and strings.xml;
rename files main.xml, aboutzoo.xml, options.xml, sightseeing.xml
add file colors.xml
Merge pull request #4 from ampatalas/android

Create welcome screen