Couple missing tests for BitArray

[kshyatt]

No description provided.

[mbauman]

Could be nice to also test !isassigned for some out of bounds ii while you're at it.

[kshyatt]

Updated the test to actually get at all the assigned indices...

[mbauman]

Appveyor failure is unrelated (but interesting — some string is empty that shouldn't be?):

Test Failed at C:\projects\julia\julia-\share\julia\stdlib\v1.1\Profile\test\runtests.jl:34
  Expression: !(isempty(str))
Error in testset Profile:
Test Failed at C:\projects\julia\julia-\share\julia\stdlib\v1.1\Profile\test\runtests.jl:41
  Expression: !(isempty(String(take!(iobuf))))
Error in testset Profile:
Error During Test at C:\projects\julia\julia-\share\julia\test\testdefs.jl:19
  Got exception outside of a @test
  LoadError: ArgumentError: reducing over an empty collection is not allowed
  Stacktrace:
   [1] _empty_reduce_error() at .\reduce.jl:216
   [2] reduce_empty(::Function, ::Type) at .\reduce.jl:226
   [3] mapreduce_empty(::typeof(identity), ::Function, ::Type) at .\reduce.jl:251
   [4] _mapreduce(::typeof(identity), ::typeof(max), ::IndexLinear, ::Array{Int32,1}) at .\reduce.jl:305
   [5] _mapreduce_dim at .\reducedim.jl:305 [inlined]
   [6] #mapreduce#535 at .\reducedim.jl:301 [inlined]
   [7] mapreduce at .\reducedim.jl:301 [inlined]
   [8] _maximum at .\reducedim.jl:650 [inlined]
   [9] _maximum at .\reducedim.jl:649 [inlined]
   [10] #maximum#541 at .\reducedim.jl:645 [inlined]
   [11] maximum at .\reducedim.jl:645 [inlined]
   [12] print_flat(::Base.GenericIOBuffer{Array{UInt8,1}}, ::Array{Base.StackTraces.StackFrame,1}, ::Array{Int32,1}, ::Int32, ::Profile.ProfileFormat) at C:\projects\julia\usr\share\julia\stdlib\v1.1\Profile\src\Profile.jl:398