Rename `HelloWorld.html` to `index.html`

Also add Chrome Frame tag to Hello World so it works in IE if GCF is installed.

This change was largely a result of some end-user usability feedback in a recent Cesium hackathon.
Add index.html for the small release zip.
Update Cesium.js index.html with external links.
Fix tab/space inconsistency.
Merge branch 'master' into helloWorld
Have the Cesium.js index.html detect if it is being ran from inside a web-browser and put up a message and link if it is not.
Fixed typo
Merge branch 'master' into helloWorld
Fix CZML cartographic handling

Remove CzmlCartographic and replace it with CzmlPosition, this causes Cartographic data to be converted to Cartesian on load, rather than every time it's needed.  This also fixed #636, which was the result of incorrect interpolation.  It also simplifies some code in DynamicPositionProperty.
Update CHANGES.md
Add tooltips to Sandcastle labeled tabs and search results.
Merge pull request #637 from AnalyticalGraphicsInc/issue636

Fix CZML cartographic handling
Fix polyline issue for straight lines.
Merge pull request #629 from AnalyticalGraphicsInc/helloWorld

Rename `HelloWorld.html` to `index.html`
Merge pull request #642 from AnalyticalGraphicsInc/sandcastle-tooltips

Sandcastle Tooltips
Merge pull request #644 from AnalyticalGraphicsInc/polylineIssue

Fix Polyline issue.