Allow certificate configurations to reference external files

This commit adds a function to the configuration.js module
to allow a pzh configuration to point to a file containing
a PEM certificate rather than forcing the PEM certificate
to be inside the JSON structure.  This will make it easier
to deploy the PZH Web Server without re-editing the
configuration files each time.

Jira issue: WP-965
Fixed prop messages schema

Added 'resp_to' as an optional field.

Jira-issue: WP-962
Fixed prop messages jasmine tests

Jira-issue: WP-962
Configuraiton changes to not set null and use undefined instead

Jira Issue: WP-961
Merge pull request #3 from jplyle/make-loading-external-certificates-easy

Allow certificate configurations to reference external files
Merge pull request #4 from ccameroni/WP-962-fix-prop-messages-validation

WP-962 fix prop messages validation
Merge pull request #6 from aldafu/WP-848-split-servicedisco

split WebinosService into its own file
clean up

declare node_moduleDir once. add missing stat var declaration.

Jira-issue: WP-1002
Remove API test pages API that are not available.

When an API module is removed we now remove the test pages for that API.

Jira-issue: WP-1002
bump version to 0.8.2