Add a maxQueueSize configuration option

[fathyb]

Ref: LIB-442

[fathyb]

Did this to avoid an useless cast from NSUInteger (long on 64bits) to int

[f2prateek]

Nice - can we add a test case for when a custom queue size is set?

[codecov-io]

Codecov Report

Merging #765 into master will increase coverage by 4.43%.
The diff coverage is 93.1%.

@@            Coverage Diff             @@
##           master     #765      +/-   ##
==========================================
+ Coverage      81%   85.43%   +4.43%     
==========================================
  Files          54       52       -2     
  Lines        2785     2616     -169     
==========================================
- Hits         2256     2235      -21     
+ Misses        529      381     -148

[fathyb]

@f2prateek pushed a test

[f2prateek]

what if somebody sets maxQueueSize to 0?

[fathyb]

Oh, good catch! I guess we have to choose from one of these behaviours (ordered with what I think is best first) :

1. forbid using maxQueueSize = 0 and throw an error in maxQueueSize setter if 0 is set
2. when maxQueueSize == 0 ignore all events
3. when maxQueueSize == 0 behave like maxQueueSize == 1

[f2prateek]

Option 4: maxQueueSize == 0 should behave like a no-op, i.e. use the default setting.

[f2prateek]

Option 5: Document that this must be > 1, and when maxQueueSize == 0 the behaviour is unspecified. I think this is reasonable for now.

[f2prateek]

Can we also document the default value here?

[fathyb]

Pushed improved docs @f2prateek

[f2prateek]

hey @fathyb - think we might need a more complicated rebase here. I'll re-assign this back to you for now!