Revert "Revert "Add in additional http request types""

This reverts commit 9e5c44f22b47fcb0d37c7b10de3b5db542424fa5.

Also, to run tests, the android:targetPackage in the
<instrumentation>needs to be set to
com.android.volley.tests (i.e., the volley_tests apk itself) because
volley is just a jar that is statically linked into the test apk.

Change-Id: I41ad41e401084b79fbf9712e24d7f7fdeb358223
Merge "Revert "Revert "Add in additional http request types"""