AltStore will now consider an update available if either:
* The source’s marketing version doesn’t match installed app’s version
* The source declares a build version AND it doesn’t match the install app’s build version
The installed app matches an app version if both maketing versions match, and the build versions match (if provided by the source).
If source is already added, the error message will list all installed apps from the source.
If adding source for first time, the error message will mention exactly which apps have been blocked from the source (if provided).
AltStore assumes all apps have unique bundle IDs per source. Weird bugs can occur when this is not the case (such as merging multiple store listings into one), so we now verify upfront whether source contains duplicate bundle IDs before saving.
