Latest version check and other improvements

[ghost]

• adds function to check for latest version now that the repo is public 😍
• adds binary name and version to http user agent used by all AWS SDK clients
• improves goroutine responsible for handling and passing in keyboard input. golang select blocks wait on multiple channels and executes the case statement of the first one it receives data from. in this case, sometimes the 50 millisecond wait was triggering when a user was in the middle of sending input. this caused random characters to sometimes not be sent. increasing the timeout means its far less likely to occur.
• minor function cleanup and reorganization

[rue-amccarthy]

neat