* Add a new socketutil module with a few helper functions that allow us to:
* Always use a sane User-Agent (previously, only Wikipedia did so)
* Set timeouts in an almost sane manner. Doing it explicitly prevents an interaction with KOSync that does crazy stuff I don't even want to try to understand.
* Unified said timeouts based on the request's intended usage (except for Wikipedia, which already had meaningful timeout values).
* Stopped using LuaSec directly, LuaSocket defers to LuaSec sanely on its own. Everything now transparently supports HTTPS without code duplication.
* LuaSettings/DocSettings: Updated readSetting API to allow proper initialization to default.
Use it to initialize tables, e.g., fixing corner-cases in readerFooter that could prevent settings from being saved.
(Fixes an issue reported on Gitter).
* LuaSettings/DocSettings: Add simpler API than the the flip* ones to toggle boolean settings.
* Update LuaSettings/DocSettigns usage throughout the codebase to use the dedicated boolean methods wher appropriate, and clean up some of the more mind-bending uses.
* FileChooser: Implement an extended default exclusion list (fix#2360)
* ScreenSaver: Refactor to avoid the pile of kludges this was threatening to become. Code should be easier to follow and use, and fallbacks now behave as expected (fix#4418).
* OPDS: Don't save an empty username.
That causes LuaSockets to try Basic auth, which is useless (and may or may not be problematic for some servers).
* Attempt to explicitly request non-compressed content.
Some servers may still refuse to obey, though.
They're breaking RFC2616 (a.k.a. HTTP/1.1) by doing so, though, meh.
* Let LuaSocket do its job.
It already handles setting up the Host header, as well as Basic authentication if both username & password are set.
Remember, it's life +70 in US & EU, life +50 is Canada.
(It's actually slightly more complex than that, and some periods of
time/countries may use a far longer term. IANAL).
