moved library into /library, created a new /sample gradle project, support for sending email

+ moved library into `/library`
+ created a new `/sample` gradle project
+ defined `@color/libpastelog_confirmation_background`
+ produces Maven artifacts in `/library/build/mvn-repo`
+ supports sending of email via installed Android email apps
+ touched up strings for ease of indexing in Transifex
+ added copyright where missing
+ updated README