avoid using BlockStatement since it's too generic.

also introduced the option to set options based on parent type and node key.

this will make some of the process simpler but just not sure if end user should
be facing this kind of setting...
change logic so special nodes are handled by a separate file

also make sure settings are set by a single "alias" to make the config process
simpler (will be less flexible but match esformatter config).

also document transformNode, sanitize, and remove BlockStatement from readme
example.
split tests into individual files

makes it easier to read errors on the console and also simpler to isolate the
problems.
add test for ConditionalExpression and fix behavior
moar tests
0.2.0