chore(progress-circle): fix invalid link in readme

Closes #247

Author: robertodecurnex

src/components/progress-circle/README.md

@@ -1,7 +1,7 @@
 # md-progress-circle
 
 `md-progress-circle` is a component for indicating progress and activity, matching the spec of 
-[Material Design Progress & Activity](https://http://www.google.com/design/spec/components/progress-activity.html).
+[Material Design Progress & Activity](https://www.google.com/design/spec/components/progress-activity.html).
 
 ### Progress Modes
 
@@ -48,4 +48,4 @@ Properties:
 | ---       | ---                               | --- |
 | `color`   | `"primary"|"accent"|"warn"`       | The color palette of the progress indicator |
 | `mode`    | `"determinate"|"indeterminate"`   | The mode of the progress indicator |
-| `value`   | number                            | The current progress percentage for determinate indicators |
+| `value`   | number                            | The current progress percentage for determinate indicators |