[add] Use throttleFirst operator

[add] Refactor HttpAsyncConnection of Sprout

[add] throttleLast

[add] meeting

[add] JSONIC, GSON

[update] README.md

[add] flatmap

[add] empty, flatmap

[add] map

[add] error

[add] timer

[add] interval

[add] range

[add] fromArray

[add] Just

[add] Constructor without arguments

[add] Debug subscriber

[update] README.md

[update] README.md

[update] README.md

[update] README.md

[update] README.md

[update] README.md

[update] README.md

[fix] Typo

[update] README.md

[update] README.md

[update] README.md

[add] Observable

[add] Thread util