#642: Action sheet added on click of info button
Merge branch 'issue642' of https://github.com/dhanya/paco into review/642
#642 add welcome_paco.html to project, refactor PacoWebViewController and fix a copy-paste bug, change PacoInfoView to UIActionSheet to achieve a better native UI experience
#642 code refactor to remove legacy PacoUserGuideWebViewController