ConnectionManager accepts gzip header; reads from sharedPrefs
Add 'Compress Data' option to settings
Set a Crashlytics key instead of logging
Send 'Accept-Encoding: gzip' header for WebView requests as well
Merge pull request #63 from pkillian/issue-60_support-for-gzip-header

Resolves issue #60; support for `Accept-Encoding: gzip` header added.