Provide an undefined identity by default, instead of
an Unknown User. This suppresses display of identity-related
features (such as the identity indicator) while still
providing a default implementation of the identityService
for platform components to utilize. nasa/openmctweb#99
Add general structure for Open MCT Web, including
top-level and second-level directory structure.
README files are included to explain the role of
each directory; markdown is used to allow for
richer display when viewer support is present.
WTD-519.
