Fix irregular ios version by using getPlatformVersionsFromFileSystem

[knight9999]

This PR is like #35.

Instead of the webpack dependent method __non_webpack_require__ ,
This PR uses the getPlatVersionsFromFileSystem method which is same as the one defined in cordova-lib/platform_metadata.js.

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PR #35 is the following.

iOSPlatform version should be the semver form, like "4.4.0".
However, If the user add platform ios by using the directory name or git:// case, like

cordova platform add /Home/user/cordova/ios/cordova-ios4.4.0

The iOSPlatform version is Home/user/cordova/ios/cordova-ios4.4.0 not 4.4.0.
(See
https://github.com/apache/cordova-lib/blob/master/src/cordova/platform_metadata.js
and its comment above the getVersions method)

In such case, this plugin hook script does not work.

This pull request, the correct iOSPlatform version is obtained by accessing platform/ios/cordova/version file.

[akofman]

Thanks ! Before merging it, I'm just going to check with the Cordova team if it is possible to expose this function. I don't understand why it's not the case and this will prevent us to copy/paste their sources.

[knight9999]

I see. Exposing the function getPlatVersionsFromFileSystem is usable.

[Mischa1610]

For me/us would this Pull Request be also pretty important because we need to use the master branch for cordova-ios because there are fixes regarding XCode 9 and they are not sure when a new version of cordova-ios will be released.

[jcesarmobile]

This probably fixes #43

[akofman]

You're right ! I'm fixing the conflicts and merge this one.

[akofman]

Squashed and merged manually. thx @knight9999 and sorry for the late.