Avoid setting event cfgs which are same as defaults, or don't matter.

a) queuable:false - this is the default value, no need to specify it.
b) silent:true - this only impacts debug builds.

This commit is based on the event-perf-nolisteners work. This just means there's less
to iterate through when mixing configs. Not a massive/noticeable perf
improvment, but cleans things up regardless. May help with older/slower browsers.

Testing
-------

All pass.

[Total]: Passed: 10717 Failed: 0 Total: 10802 (ignored 85) (8 minutes, 18 seconds)

Numbers (Chrome 25)
------------------

This Commit:

Base x 15,821 ops/sec ±2.43% (87 runs sampled)
MyBase x 15,401 ops/sec ±2.11% (93 runs sampled)
MyBase with 10 simple value attributes x 10,244 ops/sec ±1.47% (91 runs sampled)
MyBase with 20 varied attributes x 4,937 ops/sec ±2.79% (77 runs sampled)
MyModel with 2 ad-hoc attrs x 13,827 ops/sec ±1.35% (94 runs sampled)

Prior Commit:

Base x 15,173 ops/sec ±2.47% (89 runs sampled)
MyBase x 15,100 ops/sec ±2.74% (91 runs sampled)
MyBase with 10 simple value attributes x 10,235 ops/sec ±2.11% (90 runs sampled)
MyBase with 20 varied attributes x 4,936 ops/sec ±2.50% (81 runs sampled)
MyModel with 2 ad-hoc attrs x 13,588 ops/sec ±2.06% (89 runs sampled)