Fix text escaping
Font size values less than 160 are taken as defined in pixels
Fix and optimize text positioning and autosizing
Fix static text rendering
Reduce number of text updates sent
Ensure line metrics before calculating bounds
Reduce text updates even more
Merge pull request #1458 from mbebenita/nat

Fix stage align settter and make shell tests pass again.
Adds support for alpha blending in copyPixels.
Merge pull request #1453 from tobytailor/nat

More text related fixes
Text field stubs.
Nicer image loading error message.
Don't show terminal line times by default.
Merge branch 'nat' of https://github.com/mozilla/shumway into nat