[TIMOB-10222] iOS: Implement maxLength for TextArea

[vishalduggal]

Test is in JIRA

[WhichKatieDid]

CR approved, might have issues when pasting in text areas, but will double-check in FR.

[WhichKatieDid]

FR rejected. Having maxLength set before the view is added to the view hierarchy causes value not to be applied.

var win = Ti.UI.createWindow();
var txt = Ti.UI.createTextArea({
top: 150,
height: 100,
width:300,
backgroundColor: "white",
value: '123456789'
});
txt.maxLength = 10;
var button = Ti.UI.createButton( {title: "set max length to 10"});
button.addEventListener('click', function(e) {txt.value = '12345678901234567890';});
Ti.API.info("maxLength: " + txt.maxLength);
win.add(txt);
win.add(button);
win.open();

Other issue: When you set a value to over the maxlength, it's truncated. If the user pastes into the textfield and it'd go over the maxlength, the entire paste is rejected outright. This should probably be made consistent.

[vishalduggal]

Ready for review

[WhichKatieDid]

CR and FR passed. Merging...