Add option to only run dwc to get warnings and errors, but not emit any code.

Review URL: https://chromiumcodereview.appspot.com//14746007
Preserve package: imports in web ui generated code

R=jmesserly@google.com

Review URL: https://chromiumcodereview.appspot.com//14761006
fix warnings found by dartanalyzer

R=jmesserly@google.com

Review URL: https://chromiumcodereview.appspot.com//14935006
Keep _root for a deprecation period

R=jmesserly@google.com

Review URL: https://chromiumcodereview.appspot.com//14555008
release 0.4.7+2
starting

BUG=

Review URL: https://chromiumcodereview.appspot.com//14588010
release 0.4.7+3

BUG=

Review URL: https://chromiumcodereview.appspot.com//14654004
Fixed bugs to work with 0.5.7+1

BUG=

Review URL: https://chromiumcodereview.appspot.com//14690015
constrain to latest SDK

BUG=

Review URL: https://chromiumcodereview.appspot.com//15101002
work around xtag issue on bleeding_edge

R=alanknight@google.com

Review URL: https://chromiumcodereview.appspot.com//15080008
release 0.4.8+1
Update README.md
custom pseudo-element work

BUG=

Review URL: https://chromiumcodereview.appspot.com//14312011
Version 0.4.8+2

BUG=

Review URL: https://chromiumcodereview.appspot.com//15747002
Use new csslib supporting nested rules and pseudo-elements

BUG=

Review URL: https://chromiumcodereview.appspot.com//15738008
v0.4.8+3

BUG=

Review URL: https://chromiumcodereview.appspot.com//15744008
Fixed style tag emitted if scoped and fixed src attribute for image, etc. not being transformed

BUG=

Review URL: https://chromiumcodereview.appspot.com//15740026
Version 0.4.8+4

BUG=

Review URL: https://chromiumcodereview.appspot.com//16126009
Fixes for SDK 0.5.12

R=jmesserly@google.com

Review URL: https://chromiumcodereview.appspot.com//15645006
Update README.md