closes #743, Support non-EZproxy proxies

closes #831, transparent EZProxy support
adds a proxy pane to the preferences
asks before saving proxies to the DB (to avoid the potential phishing risk #831 would otherwise pose)

userdata.sql

@@ -1,4 +1,4 @@
--- 38
+-- 39
 
 -- This file creates tables containing user-specific data -- any changes made
 -- here must be mirrored in transition steps in schema.js::_migrateSchema()
@@ -254,4 +254,19 @@ CREATE TABLE highlights (
     dateModified DATE,
     FOREIGN KEY (itemID) REFERENCES itemAttachments(itemID)
 );
-CREATE INDEX highlights_itemID ON highlights(itemID);
+CREATE INDEX highlights_itemID ON highlights(itemID);
+
+CREATE TABLE proxies (
+    proxyID INTEGER PRIMARY KEY,
+    multiHost INT,
+    autoAssociate INT,
+    scheme TEXT
+);
+
+CREATE TABLE proxyHosts (
+    hostID INTEGER PRIMARY KEY,
+    proxyID INTEGER,
+    hostname TEXT
+    FOREIGN KEY (proxyID) REFERENCES proxies(proxyID)
+);
+CREATE INDEX proxyHosts_proxyID ON proxyHosts(proxyID);