Pr/bug fixes (single-spa#167)

* Fixes single-spa#166

* Fixes single-spa#165.

* After fixing single-spa#165 these tests needed to be fixed.

* For IE support I'm using indexOf

3.7.0 (single-spa#153)

* Pr/new api (single-spa#137)

* Brute force removing references to children from the application

* Renaming to registerApplication

* registerApplication

* Brute force updating documentation

* Fixing tests that were using `unloadChildApplication`

* appName not childAppName

* Updating docs

* Updating docs

* updating tests

* Updating test variable names

* Fixing all remaining refs to child-apps/child apps/child app

* Pr/decrecation notice (single-spa#138)

* Adding back old API's along with deprecation notice

* Adding documentation marking the api's as deprecated

* Hahaha whoops.

* Pr/single spa config (single-spa#139)

* actually upping the version number

* Updating documentation for root-application to be called single-spa-config

* Updating Root Application file to call out the name change explicitly and why

* Completing documentation changes

* A few more documentation changes

* Found one more reference I missed

* Global find replace failed me here. Fixing a bunch of small grammar and sentence issues.

* Registering applications using a configuration object revision 1 (single-spa#143)

* Registering applications using a configuration object revision 1

* Spaces

* Pr/tabs spaces (single-spa#144)

* Turning all tabs into spaces

* Fixing duplicate import error

* spaces instead of tabs for all .spec files

* tabs to spaces in additional files I missed (single-spa#146)

* Pr/adding documentation on using applications for registration (single-spa#152)

* small change here, the docs were ignoring the second argument

* Adding an explanation of using the application as the second argument.
- Putting existing section on the loading function as a sub section of the new section on either loading function or Application
- Adding example of inline application definition.

* Fixing capitalization on files

* More tiny capitalization changes

3.6.1

3.6.0

3.5.0