Refactors Calibre Wireless Device & Calibre Library (#404)

Our esp32 consistently dropped the last few packets of the TCP transfer
in the old implementation. Only about 1/5 transfers would complete. I've
refactored that entire system into an actual Calibre Device Plugin that
basically uses the exact same system as the web server's file transfer
protocol. I kept them separate so that we don't muddy up the existing
file transfer stuff even if it's basically the same at the end of the
day I didn't want to limit our ability to change it later.

I've also added basic auth to OPDS and renamed that feature to OPDS
Browser to just disassociate it from Calibre.

---------

Co-authored-by: Arthur Tazhitdinov <lisnake@gmail.com>
Co-authored-by: Dave Allie <dave@daveallie.com>

src/activities/settings/CategorySettingsActivity.cpp

@@ -103,7 +103,7 @@ void CategorySettingsActivity::toggleCurrentSetting() {
         updateRequired = true;
       }));
       xSemaphoreGive(renderingMutex);
-    } else if (strcmp(setting.name, "Calibre Settings") == 0) {
+    } else if (strcmp(setting.name, "OPDS Browser") == 0) {
       xSemaphoreTake(renderingMutex, portMAX_DELAY);
       exitActivity();
       enterNewActivity(new CalibreSettingsActivity(renderer, mappedInput, [this] {