fix convert(Int64,::BigFloat) bug on 32-bit systems (closes #8318)
move Base.random.__init__ to zero-arg srand(); fixes #8313
fix rationalize test failure on 32-bit systems
Merge pull request #8321 from JuliaLang/mn/8318

fix a couple of 32-bit bugs
Merge pull request #8320 from davidssmith/srand

move Base.random.__init__ to zero-arg srand(); fixes #8313
Documentation for zero argument srand() #8320