Add emailCiam setting to OIDC Connector for supporting an ID token
that does not contain the email claim.

*: update examples to hold valid client secrets for no-db mode

connector: add uaa connector

server: when registering a user, set user name if OIDC identity contains one

This commit adds support for dex to authenticate users from a
CloudFoundry User Account and Authentication (UAA) Server.

Fixes: #538

Fix typo in dexctl parameter

When automatically registering a user from an IP that provides
a `DisplayName`, set it on the created user so that JWT we create
contain a meaningful `name` field.

user api: accept bearer tokens with multiple audiences

*: cleanup containers generated during tests to avoid deploy conflicts

*: fix path to email config in dockerfile

*: try to fix travis deployments by adding script with no arguments

Fix standup-db.sh

Allow dex to work at non base url

connector: fix path that connectors listen on

When Dex uses a non-root issuer URL, it current assumes that all
path prefixes will be trimmed by an upstream proxy (e.g. nginx).
This means that all paths rendered in HTML will be absolute to the
prefix, but the handlers still listen at the root.

Connectors are currently the only component that registers at a
non-root URL. Make this conform with the rest of Dex by having the
server determine the path the connector listens as rather than the
connector itself.

backend: add absolute path to template links

fixes: #502

Add a new template function called `absPath` that converts relative
paths to absolute paths based on the issuerURL. The template function
can be used in templates like:
````html
<a href="{{ .MyRelativePath | absPath }}">
````

cmd: update flag defaults for dev mode

Updates flags in dex-worker for no-db mode to work with default static
files.

*: depricate --email-from flag and move to email config files

Add groups scope and LDAP implementation

connector: remove erroneous logging statement

Use "plain" auth if and only if username and password are provided.

Parse port from "host" field if it's provided.

docs: fix various typos & Markdown lint issues