Feature/prevent exec on synthetic constructors

[faradaj]

Just like preventing synthetic methods' logging (resolved in #112), synthetic constructor of a @DebugLog annotated inner class also should not be logged by Hugo.

Note: When the private constructor of an inner class is used, in addition to the synthetic constructor, an empty class will be created by compiler. At least for now, this is not a problem for Hugo. (i.e. Hugo is interested in methods and constructors.)

To demonstrate, access modifier of Charmer class' constructor is changed to private.

Before this, Hugo was logging for Charmer class' synthetic constructor too:

01-20 18:30:26.904    4298-4298/com.example.hugo V/Charmer﹕ ⇢ <init>(name="Jake")
01-20 18:30:26.905    4298-4298/com.example.hugo V/Charmer﹕ ⇠ <init> [0ms]
01-20 18:30:26.905    4298-4298/com.example.hugo V/Charmer﹕ ⇢ <init>(x0="Jake", x1=null)
01-20 18:30:26.905    4298-4298/com.example.hugo V/Charmer﹕ ⇠ <init> [0ms]

With this, Hugo now logs:

01-20 18:31:24.261    8835-8835/com.example.hugo V/Charmer﹕ ⇢ <init>(name="Jake")
01-20 18:31:24.261    8835-8835/com.example.hugo V/Charmer﹕ ⇠ <init> [0ms]

[JakeWharton]

Love it. Will merge when build passes.

[faradaj]

Great and :+1: for super-fast response as this should've been already resolved within #112 :)

[JakeWharton]

I always forget about the constructor synthetics too, or I would have commented on that original one.