Resolve "Release 0.9.1"

Closes #20, #17, #18, #12, #16, #15, #14, #11, and #10

See merge request extdev/selfregistration!4

Resolve "Create salted password on client side"

Closes #5

See merge request extdev/selfregistration!3

Resolve "Use CreateHelper Class"

Closes #6

See merge request extdev/selfregistration!2

Resolve "Implement FrontendUserController->Create()"

Closes #2

See merge request extdev/selfregistration!1