[HTTPS-Everywhere] Speeding up Firefox start with SQLite

[Jacob Hoffman-Andrews]

Here's a branch I made to experiment with putting rulesets into an 
SQLite db:
https://github.com/jsha/https-everywhere/compare/sqlite.

It works pretty well. Startup is very fast, and URLs get rewritten 
correctly. You can try it yourself here: 
https://jacob.hoffman-andrews.com/hacks/https-everywhere-jsha-sqlite-demo.xpi 
(and .asc for sig)

The downside is that we hit the DB pretty frequently, which slows down 
browsing when you hit new sites. Once a given domain has been checked 
for in the DB, we won't re-check. Probably the solution here is to load 
all the targets into memory at startup.

Let me know what you think!