* Add ksonnet version to version endpoint
I needed to move config.go out of the cli package to fix a circular dependency.
* Remove ksonnetVersion field from the ArgoCD version struct
This change implements SSO support.
dex is run as a sidecar to the ArgoCD API server, which fronts dex using a reverse proxy. The end result is that the ArgoCD acts as an OIDC provider serving under /api/dex. The login flow begins at /auth/login, which redirects to the Dex's OAuth2 consent page and ultimately directed to the IdP provider's login page, where they enter their credentials. After logging in, the OAuth2 redirect flows back to the client app, ultimately reaching /auth/callback, where the OIDC token claims are signed, and persisted in the users's cookie.
The dex configuration YAML is formulated during startup (through the argocd-util utility), with the configuration values taken from the argocd-cm configmap and the argocd-secret.
The build process was refactored to build argocd-util statically, so that it could be run inside off-the-shelf dex, which is built from alpine. Also, build speed was improved by expanding the default make targets in the Dockerfile, to avoid rebuilding each binary from scratch
Session management was refactored to use more bare-bones jwt library constructs, so we could reuse code from the user/password flow vs. OAuth2 flow.
* Initial SSO support. Run dex as sidecar. Generate dex config from ArgoCD cm and secret
* Sign and write SSO claims to JWT cookie during SSO login. Refactor session manager
* Build argo-util statically so it can run in dex sidecar. Redirect after SSO login
* Simplify app creation process to not require communication to dex gRPC server
* Refactor local ~/.argocd/config to be similar to kube configs
* `argo login` will detect TLS issues and prompt user before writing config
* version server is unauthenticated and `argo version` will report server version
* Re-arrange utilities into more granular packages
* Simplify config manager interface into just Get() and Save()
* Support installation into different namespace
* Combine all secrets into single secret
* Use a hard-wired configmap name
* Admin username is no longer configurable
