Improve documentation around HostnameVerifier

Explain usage of HostnameVerifier / HttpsURLConnection.

Bug: 126851476
Test: make docs / visual inspection
Merged-In: I6bc86f8e7efc47521316d41e07ef546ea995061c
Change-Id: I6bc86f8e7efc47521316d41e07ef546ea995061c
(cherry picked from commit 9f5e6f22bdc086ee0396f01556e3367c621737c0)
1 file changed