fix(README): Link syntax

Since wordpress also doesn't allow brackets in attribute values, first
replace `((` and `))` by `[` and `]` before expanding the shortcodes.

Expands the README to full documentation, and renames internal functions
to make more sense.

Resolves #10.

Co-authored-by: Glen Whitney <glen@studioinfinity.org>
Reviewed-on: #11

README.md

@@ -61,7 +61,7 @@ An example that puts this all together:
 
 would present the TablePress table with id 2 but with any row in which magic tags appeared into a sequence of rows with those tags expanded, for each record returned by `pods('budget', [ 'where' => "account.meta_value = 'Sales'" ])`
 
-See the [pods() documentation][https://docs.pods.io/code/pods/] for more on possible values for the where parameter.
+See the [pods() documentation](https://docs.pods.io/code/pods/) for more on possible values for the where parameter.
 
 - pod_dump=true