[TIMOB-11026] Fix builder.py for min version support

[vishalduggal]

QE should do FR
TICKET

[eric34]

Pull accepted:
Verified setting min iOS below 4.0:
[INFO] Minimum iOS version 3.2 is lower than 4.0: Using 4.3 as minimum
Verified build with iOS 6 will install on 4.3+ and not on 4.0.2 device

Verified setting to iOS 9.9 will set to min 6.0
[INFO] Minimum iOS version 9.9 is greater than 6.0 (iphone_version): Using 6.0 as minimum
Verified this build will install only on iOS 6 (not 4.0.2, 4.3.3, or 5.1)

Verified bogus setting "jeff cool cold game" for min setting defaults to 4.3 (Xcode 4.5)
[WARN] Could not parse value jeff cool coldgame as 'x.x' version: Setting to default
[INFO] Minimum iOS version 0.0 is lower than 4.0: Using 4.3 as minimum

Verified setting to 5.0 and got expected results

Repeated above with Xcode 4.4.1 (Min iOS) and included packaging both with ad-hoc and app store distribution