Fix: No more crashing/skipped changes for certain changes

[dmsnell]

See: Simperium/node-simperium#91
See: google/diff-match-patch#80

Possibly fixes:

• Windows: Failure to sync all notes on version 1.3.4 (Windows 10) #1117 (Chinese surrogate pairs breaking sync?)
• Typing Korean results in almost half of the letters being automatically deleted #1511 (Same but for Korean)
• New WEB version not synced at times #1562 (error in diff_fromDelta() - maybe a length-counting issue in the Python version)

Maybe related but likely not:

• Typing CJK after a Tab character can crash the app #780 (crashing app with characters after tab)
• Application often crashes when backspace is pressed in windows7 #890 (crashing app on backspace after characters)

Other repos:

• Simplified Chinese characters simplenote-android#436 (Issue with specific Simplified Chinese characters)
• Korean Characters not Printing Correctly Consistently Simplenote-United#33 (Korean characters being messed up - like in Typing Korean results in almost half of the letters being automatically deleted #1511)

There have been certain cases where consecutive surrogate pairs crash
diff-match-patch when it's building the delta string. This is
because the diffing algorithm finds a common prefix up to and including
half of the surrogate pair match when three consecutive code points
share the same high surrogate.

// before - \ud83d\ude4b\ud83d\ue4b
// after  - \ud83d\ude4b\ud83d\ue4c\ud83d\ude4b
// deltas - eq \ud83d\ude4b\ud83d -> add \ude4c -> eq \ud83d \ude4b

This crashes when trying to encode the invalid sequence of UTF-16 code
units into URIEncode, which expects a valid Unicode string.

After the fix the delta groups are normalized to prevent this situation
and the node-simperium library should be able to process those
problematic changesets.

This patch updates the dependency on the patched version of
node-simperium.

Testing

Follow the sequence described in Automattic/simplenote-macos#397

Add a new note
Enter the following emojis: ☺️🖖🏿
Insert the following emoji in between: 😃

In develop you should notice an exception in the dev tools showing that the update failed. Your updates will continue to fail for that note until the emoji sequence is removed. If you clear the browser cache or signout/signin the changes, even those you made after the emoji, will disappear.

In this branch the update should work as expected. If you clear the browser cache or signout/signin the changes will remain.

Before

After

[belcherj]

Let's get this merged and test heavily on Develop.