statement unittest v2

[monkyyy]

`unittest => 1==1;`
`unittest math_still_works => 1==1;//generates ddoc`

I see roughly 3 criticisms to my last suggestion

1. unittest without docs are bad
2. this is a bug; that should already work (???)
3. we may want agrumented unittests in the future

so handling the arguments out of order

# 2.

what? whatever i'll simplify the syntax

# 3.

by not using ()'s I assume it will leave open the door for 
whatever this theory is

# 1. docs

I dont care about this in the slightest but... whatever

`unittest [name] => code;`

if optional `name` exists generate a header and `code` in ddoc

name will replace'_'s with spaces, put it in a header followed by 
a code block of the code

so given this code

```d
/**
* a very important function
*/

auto foo=>[1,2,3,4,5];
unittest foo_returns_an_array=>foo==[1,2,3,4,5];

```

will generate the docs

```md
# foo
## int[] foo()

a very important function

## foo returns an array

```d
foo==[1,2,3,4,5];
```

```