Add system property com.nokia.mid.batterylevel
Add AudioRecorderMidlet
Implement audio capture api
Fix the timing issue when media permission prompt is not disabled.

Also add audio-capture to permissions of manifest.webapp.
Merge pull request #633 from PinZhang/pzhang/batterylevel

Add system property com.nokia.mid.batterylevel
Merge pull request #619 from PinZhang/pzhang/pr-audio-capture-rebase

Implement audio capture API