Move to \MarketoApi namespace

[Jaesin]

This should be done at the time of a 1.0 release but not before.

[itmayziii]

@Jaesin Why not before?

[itmayziii]

@Jaesin I have added some notes for the project, let me know what you think about those TODO items. I agree we need more testing around everything. In my opinion I think we should aim to cover every endpoint Marketo offers in their REST services. That would mean we have a lot more to add and we might consider breaking up the Client.php file, I was thinking of breaking it up like this?

• Src
  • Request
    ( This is the way Marketo breaks up the endpoints in the documenation)
    • Lead Database
      • Companies.php
      • Leads.php
      • etc...
    • Asset
      • Channels.php
      • Emails.php
      • etc...
    • Authentication
  • Response
    • All the response classes.php

[Jaesin]

As far as not chaging the namespace before a 1.0, we are using this library in some projects that will need minor refactoring. That said, I think we need to create a point release.

As far as implementing new client calls. I would like to see us writing less code and using the services.json file as much as possible. The reason being is that there will be changes in guzzle services for major version upgrades and I plan to make this library guzzle 6 compatible. The services.json file hasn't changed so a guzzle major version upgrade should be very easy as long as there isn't much code.

For guzzle 6, we need a middleware for oauth2 and the services.json file. It would be quite nice if that was all we needed.

guzzle/guzzle-services#109
commerceguys/guzzle-oauth2-plugin#29

[PancakeTornado]

README.md will also need its namespace references updated.