26:3 Adventure to teach player about terminal

#139 (closed) Story 26, Task 3: Make an adventure asking the player to type 'help' into the terminal. Typing 'help' would print a message back to the terminal describing the different commands and other important information the player might need to know.

1. Add adventure under OnRamping Adventures in AdventuresForTest.java.
2. Create a CommandTerminalTextHelp class to be used by the adventure.
3. Create a quest completion flag when 'help' command is typed for the first time.