include tests in Rstudio builds (for test coverage).

test trim()
move shuffle from generate test cases to util.r
rename flatten_list
respect min and max for numeric and integer generation
new random test integer function
new allIsInteger function
updates to areIntegers
extensive tests to define the behavior of allIsInteger and areIntegers (TODO: make consistent NA behavior with allIsNumeric, etc)
add_time_to_date bugfixes
na.rm for isValidTime
permute - beautiful little function to generate (factorial) combinations of a vector
isFlat tests whether a list has sub-lists.
more trim tests
merge completed