add configurable flisp profiling / timing code

[vtjnash]

@JeffBezanson thoughts on whether / how we should put this in core?

[vtjnash]

bump

[vtjnash]

for example, here's a sample usage for evaluating lowering timings:

begin
           ccall(:fl_profile, Void, (Cstring,), "julia-expand")
           ccall(:fl_profile, Void, (Cstring,), "julia-expand-macros")
           ccall(:fl_profile, Void, (Cstring,), "julia-expand0")
           ccall(:fl_profile, Void, (Cstring,), "julia-expand1")
           ccall(:fl_profile, Void, (Cstring,), "resolve-scopes")
           ccall(:fl_profile, Void, (Cstring,), "analyze-variables!")
           ccall(:fl_profile, Void, (Cstring,), "closure-convert")
           ccall(:fl_profile, Void, (Cstring,), "linearize")
           ccall(:fl_profile, Void, (Cstring,), "renumber-slots-and-labels")
           ccall(:fl_profile, Void, (Cstring,), "lift-toplevel")
           ccall(:fl_profile, Void, (Cstring,), "map-cl-convert")
           ccall(:fl_profile, Void, (Cstring,), "cl-convert")
           ccall(:fl_profile, Void, (Cstring,), "expr-find-all")
           ccall(:fl_profile, Void, (Cstring,), "lambda-optimize-vars!")
end
ccall(:fl_show_profile, Void, ())
ccall(:fl_clear_profile, Void, ())

[StefanKarpinski]

Might want to restart the OS X tests?

[vtjnash]

would need to rebase to pick up the new .travis file