Not allowing setObjectId() in ParseInstallation

[hermanliang]

When I deal with the issue #607, I found another issue about ParseInstallation.
(It's a very special case, generally should not happen.)

ParseInstallation installation = ParseInstallation.getCurrentInstallation();
installation.setObjectId(null);
// put some parameters here
installation.save();

I originally expected another installation data will be created in the server.
But the installation data is updated successfully and doesn't return any exceptions.
The objectId of cached installation data is also cleared (null).
It seems parser server will refer to 'installationId' when updating the installation data.
In this case, the installation data is not re-created when it is deleted on the server. (will throw Code 135: MissingRequiredFieldError exception)
I think it should be restricted the usage of setObjectId() in ParseInstallation.

[codecov]

Codecov Report

Merging #611 into master will decrease coverage by 0.01%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master     #611      +/-   ##
============================================
- Coverage     52.58%   52.56%   -0.02%     
  Complexity     1664     1664              
============================================
  Files           131      131              
  Lines         10138    10139       +1     
  Branches       1407     1407              
============================================
- Hits           5331     5330       -1     
- Misses         4368     4369       +1     
- Partials        439      440       +1

Impacted Files	Coverage Δ	Complexity Δ
...rse/src/main/java/com/parse/ParseInstallation.java	75.96% <100%> (+0.23%)	40 <1> (+1)	⬆️
Parse/src/main/java/com/parse/ParseObject.java	50.3% <0%> (-0.14%)	200% <0%> (-1%)

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[rogerhu]

rebase