feat: add debug.deep and debug.shallow (#37)

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### Summary

Adds API proposed by https://github.com/callstack/react-native-testing-library/pull/33#issuecomment-430302079.
Also component output is now highlighted:

<img width="259" alt="screenshot 2018-10-16 at 19 33 25" src="https://user-images.githubusercontent.com/5106466/47035614-c10efb80-d17a-11e8-99ac-00f648880008.png">


### Test plan

Added tests for `debug`.

yarn.lock

@@ -842,6 +842,11 @@ ansi-regex@^3.0.0:
   resolved "https://registry.yarnpkg.com/ansi-regex/-/ansi-regex-3.0.0.tgz#ed0317c322064f79466c02966bddb605ab37d998"
   integrity sha1-7QMXwyIGT3lGbAKWa922Bas32Zg=
 
+ansi-regex@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/ansi-regex/-/ansi-regex-4.0.0.tgz#70de791edf021404c3fd615aa89118ae0432e5a9"
+  integrity sha512-iB5Dda8t/UqpPI/IjsejXu5jOGDrzn41wJyljwPH65VCIbk6+1BzFIMJGFwTNrYXT1CrD+B4l19U7awiQ8rk7w==
+
 ansi-styles@^2.2.1:
   version "2.2.1"
   resolved "https://registry.yarnpkg.com/ansi-styles/-/ansi-styles-2.2.1.tgz#b432dd3358b634cf75e1e4664368240533c1ddbe"
@@ -6275,6 +6280,13 @@ strip-ansi@^4.0.0:
   dependencies:
     ansi-regex "^3.0.0"
 
+strip-ansi@^5.0.0:
+  version "5.0.0"
+  resolved "https://registry.yarnpkg.com/strip-ansi/-/strip-ansi-5.0.0.tgz#f78f68b5d0866c20b2c9b8c61b5298508dc8756f"
+  integrity sha512-Uu7gQyZI7J7gn5qLn1Np3G9vcYGTVqB+lFTytnDJv83dd8T22aGH451P3jueT2/QemInJDfxHB5Tde5OzgG1Ow==
+  dependencies:
+    ansi-regex "^4.0.0"
+
 strip-bom@3.0.0, strip-bom@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/strip-bom/-/strip-bom-3.0.0.tgz#2334c18e9c759f7bdd56fdef7e9ae3d588e68ed3"