Implement goog.module.get()

https://docs.google.com/document/d/1oHfNHEeVOHMxpert0NIssIuEacFh4sTQXigf6vTd1G8/edit?usp=sharing
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74405803
[Closure] Add goog.array.sortByKey for sorting objects based on key function

Probably the largest class of use cases this new function will address involves JSPB protos, the fields of which are accessed through getter methods. This precludes the usage of goog.array.sortObjectsByKey, and forces to write boilerplate comparator for goog.array.sort whenever a need arises to order JSPB protos based on some dedicated sort_key field (e.g.-- )
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74422939
[Closure] Implement goog.array.sortObjectsByKey using goog.array.sortByKey
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74426560
Allow disabling Object.seal for goog.module loaded exports using a flag, by default set to goog.DEBUG.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74544585
Extend list of Unicode address separators but use them only for internationalized email addresses.

This effectively rolls back cl/68570362. When we introduce that change I don't think we had the internationalized version yet, so applied the chinese comma as separator always. Now that we decoupled them I think it is a good idea to handle that Unicode separator as any other (i.e., only applies for internationalized addresses).

List of address separators (proposed by the internationalization team) in https://docs.google.com/a/google.com/spreadsheets/d/1yARkO1nu0gyYGs9zoVMxMkYhK1bR-wVzOoDw5uVLZGM/edit#gid=0
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74575234
Update closure locales data to include Irish (language code "ga").

All the files are generated by scripts from CLDR data.

Note that this is needed for adding Irish to Gmail.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=74606455
Merge branch 'master' of https://github.com/google/closure-library