Make tests to look a bit better

This allows us to transform

describe("CONTEXT", function()
  it("DOES SOMETHING", function()
    -- do something
  end)
end)

into

describe "CONTEXT" (function()
  it "DOES SOMETHING" (function()
    -- do something
  end)
end)

which is easier to read (and write too, no comma :) )

Uses that Lua syntactic sugar:
  function("STR")  is equal to function "STR"
and a little bit of functional programming (anonymous funcs + closures)
Merge pull request #209 from Pencioner/master

Make tests to look a bit better
fixed bug where if failures in tests happen in a very specific order then last_j will be nil, causing table.concat to throw an error.
add support for the `context` describe alias
Merge pull request #211 from Olivine-Labs/bugfix_lastj

fixed bug where if failures in tests happen in a very specific order the...
assign _TEST for `strict.lua`
Merge pull request #213 from Olivine-Labs/context

add support for the `context` describe alias
Merge pull request #214 from Olivine-Labs/strict-mode

assign _TEST for `strict.lua`