markdown fixup, addressed typos

- fixed headings to be H2's (was a bunch of H1's)
- fixed sentence case on page title
- fixed few typos

README.md

@@ -1,65 +1,64 @@
-# SharePoint Framework Extensions samples & tutorial materials
+# SharePoint Framework Extensions Samples & Tutorial Materials
 
 This repository contains the samples that demonstrate different usage patterns for the SharePoint Framework extensions.
 
 SharePoint extensions are controls that appear inside a SharePoint page but run locally in the browser. They're the building blocks of pages that appear on a SharePoint site. You can build extensions using modern script development tools and you can deploy your extensions to modern pages in Office 365 tenants. In addition to plain JavaScript projects, you can build extensions alongside common scripting frameworks, such as AngularJS and React. For example, you can use React along with components from [Office UI Fabric React](http://dev.office.com/fabric#/components) to quickly create experiences based on the same components used in Office 365 natively.
 
-# Have issues or questions?
+## Have issues or questions?
 
 Please use following logic on submitting your questions or issues to right location to ensure that they are noticed and addressed as soon as possible.
 
 * You have general question or challenge with SPFx - use [sp-dev-docs repository issue list](https://github.com/SharePoint/sp-dev-docs/issues).
 * You have issue on specific extension or sample - use [issue list in this repository](https://github.com/SharePoint/sp-dev-fx-extensions/issues).
 
-
-# Additional resources
+## Additional resources
 
 * [SharePoint Framework Extensions (preview)](https://dev.office.com/sharepoint/docs/spfx/extensions/overview-extensions)
 * [Overview of the SharePoint Framework](http://dev.office.com/sharepoint/docs/spfx/sharepoint-framework-overview)
 * [SharePoint Framework development tools and libraries](http://dev.office.com/sharepoint/docs/spfx/tools-and-libraries)
 * [SharePoint Framework Reference](http://aka.ms/spfx-reference)
 * [Visual Studio Extension for SharePoint Framework projects](https://github.com/SharePoint/sp-dev-fx-vs-extension)
 
-# Using the samples
+## Using the samples
 
 To build and start using these projects, you'll need to clone and build the projects.
 
 Clone this repo by executing the following command in your console:
 
-```
+```shell
 git clone https://github.com/SharePoint/sp-dev-fx-extensions.git
 ```
 
 Navigate to the cloned repository folder which should be the same as the repository name:
 
-```
+```shell
 cd sp-dev-fx-extensions
 ```
 
 To access the samples use the following command, where you replace `sample-folder-name` with the name of the sample you want to access.
 
-```
+```shell
 cd samples
 cd sample-folder-name
-
 ```
+
 and for the tutorials, use the following command:
-```
+
+```shell
 cd tutorials
 ```
 
 Now run the following command to install the npm packages:
 
-```
+```shell
 npm install
 ```
 
 This will install the required npm packages and dependencies to build and run the client-side project.
 
-
 Once the npm packages are installed, run the following command to start nodejs to host your extension and preview that in the SharePoint Online pages:
 
-```
+```shell
 gulp serve
 ```