Compatibility with Julia 0.3 (0.3.0-rc1) and required associated test/example updates.

This pull request is for a set of changes to allow SimJulia (and tests/examples) to be used with Julia 0.3 (0.3.0-rc1).

A number of these changes are the same as those made by Aaron Cleaver in the AaronCleaver/SimJulia.jl develop branch; however additional changes were needed for the current 0.3 release candidate, and these changes were also made on top of the latest SimJulia code.  This pull request also includes changes required to the tests / examples.

The request also includes the fix noted in issue #8

The changes included are:

/
 - modify REQUIRE file to require Julia 0.3 pre-release or greater

src/
 - replace calls to min(...) with minimum(...)
 - replace calls to max(...) with maximum(...)
 - replace calls to delete!(...) when removing by index with splice!(...)
 - replace calls to add! with push! in a number of places
 - use collect(...) when retrieving dictionary key by index
 - resolve indexing issue in filter_number function
 - avoid name clash between variable and function name (in histogram function)

test/
 - avoid name clash in calls to get(...)
 - avoid name clash in calls to buffer(...)
 - replace calls to add! with push!

All the tests / examples have been verified to run with Julia 0.3 when these changes are applied.