Remove react router as a dependency

[bcullman]

This should allow consumers to use React-Router 4 which will allow for greater code splitting of applications.

CORUI-5993

[droshev]

@bcullman the link to your JIRA requires user

[bcullman]

@droshev : those are links to SAP Concur's internal JIRA instance. we will remove the links.

[InnaAtanasova]

@bcullman , we are using react-router for the documentation components. If we separate the documentation, do you think we still need to remove react router as a dependency?

[jiawang1]

some components depends on react router: Breadcrum, Menu, tabs....

[bcullman]

@jiawang1 they will need to be re-written so that they operate using props and not a direct dependency on react-router.