Address UX feedback. Issues: #33

[yizheliu-amazon]

Issue #, if available:
#33
Description of changes:
Address UX feedback:

1. Move the Create Detector button to align with Dashboard title
2. Make sure Live Anomalies title is consistent with AnomalyResultLiveChart page
3. Change the font of "10 detectors with the most recent anomaly occurrence" to that of "Detector with the most recent anomaly occurrence" above
4. Reduce the height of Live chart by half, in order to allow the user see more content without scrolling down. To be consistent with AnomalyResultLiveChart page, I have checked with Yaliang, since he reduces to 200px, I will reduce height to 200px as well.
5. Make sure sunburst chart covers 60% width, while detector/feature list covers 40% width(Done by PR 30)
6. Make sure sunburst chart's space between upper and lower border is only 20px

After fix, page looks like below:

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[ylwu-amzn]

Add copyright header

[yizheliu-amazon]

will add it.