Move alias and function creation to .gitpod.Dockerfile

[apolopena]

Describe the bug

Any aliases written to .bashrc or .bash_profile will only work out of the box from the Init terminal, other currrently open terminals (not new ones though) will not have those aliases or functions until a new terminal (in the case of .bashrc) or .bash_profile is sourced.

Screenshots

Steps to reproduce

1. Create a new repo from the workspace
2. run debug-on in an currently open terminal that is not the Init terminal/

Expected behavior

Any terminal should have all the aliases and functions available that were written in during the gitpod initialization.

Additional information

Eventually this system will need to be refactored to use $HOME/.bashrc.d so that .bashrc does not become too bloated.

[apolopena]

Git aliases are still written to ~/.gitconfig in the init task but that can stay that way for the foreseeable future.