Inconsistent compile / transpile API

[jakub-g]

In #213 I wrote some very basic compile/transpile guide with pure Node (and just added a link at the end to a sample repo where this is done with Gulp).

There's some inconsistency in the code though, because hashspace exports just the compiler but not transpiler, so the code in the docs I wrote goes like this:

var compiledHS = require('hashspace').compiler.compile(inputHSCode, inputHSFileName).code;

var transpiledJS = require('hashspace/hsp/transpiler/transpile')(inputJSCode, inputJSFileName);

The second difference is that compile returns an object with code and some other props while transpile returns a string. IMO it would be good to have them consistent.