Path lookups work, all "gets" use ctx.get

1. Path lookups work:

  Instead of having to do something like

```
{#myArray}
  {.}: {#data}{val}{/data}
{/myArray}
```

you can do

```
{#myArray}
  {.}: {data.val}
{/myArray}
```

2. It made sense for all references (gets) to use ctx.get, instead of get and getPath

This commit also adds unit tests as defined by @rragan for #271