Bug 731074 - console.log not working from a panel's script

- Added web console methods to plain-text console
- Added plain-text console to web pages in documents not in a tab
- Updated unit test
Addressed review's comment and suggestion.
Add link to style guidelines

For the lazy, like myself.
fixing private-browsing test for fennec, which cannot open new windows
Merge pull request #722 from ZER0/panel-console/731074

Fix Bug 731074 - console.log not working from a panel's script r=@Gozala, @ochameau
Merge pull request #742 from erikvold/fennec-pb-test-fixes

Fix Bug 834089 Fixing private-browsing test for fennec, which cannot open new windows r=@zer0
Merge pull request #740 from gregglind/patch-4

Add link to style guidelines
Bug 832590 - (sdk/test) Need a way to extend test timeout time
Merge pull request #744 from ochameau/max-timeout@832590

Fix Bug 832590 - (sdk/test) Need a way to extend test timeout time
Bug 834944 - require("api-utils/utils/data").getChromeURIContent("...") throw 'deprecatedUsage is not a function'
Merge pull request #745 from ochameau/io-data@834944

Bug 834944 - require("api-utils/utils/data").getChromeURIContent("...") throw 'deprecatedUsage is not a function' r=@erikvold
Merge branch 'master' of https://github.com/mozilla/addon-sdk into 828746