Add Android overlay support to README

[Menardi]

Platforms affected

N/A

What does this PR do?

Updates the README to:

• Add Android as a supported platform for StatusBarOverlaysWebView - support for this was added in v2.2.3 but never added to the README
• Remove references to iOS 7 where it is implied to be the latest version of iOS. It's not likely that anyone now cares about iOS 7!

What testing has been done on this change?

N/A

Checklist

• Reported an issue in the JIRA database
• Commit message follows the format: "CB-3232: (android) Fix bug with resolving file paths", where CB-xxxx is the JIRA ID & "android" is the platform affected.
• Added automated test coverage as appropriate for this change.

[ManigandanRaamanathan]

Overlay is not working on android. Always gets a black status bar

[ManigandanRaamanathan]

Using StatusBar.overlaysWebView(true) makes the entire statusbar background invisible but the content of the page obstruct (goes/overlays through) the status bar since there is no status bar

[Menardi]

@ManigandanRaamanathan If you want a semi-transparent status bar, you can do this, which is actually part of the docs improvement in this PR:

StatusBar.overlaysWebView(true);
StatusBar.backgroundColorByHexString('#33000000');

Otherwise, if you think there is an actual bug, you should file it at the Cordova JIRA.

[ManigandanRaamanathan]

Will it work after the latest commit?

The below fix did not work:-
overlaysWebView(true);
StatusBar.backgroundColorByHexString('#33000000');

[janpio]

@ManigandanRaamanathan http://issues.cordova.io is the correct place to talk about this, not a PR. Thank you.