Field Describe limit reached with SmartFactory.

[abhinavguptas]

This limit is easy to reach if you are writing a test case to verify bulk nature of triggers etc. For ex. code below will crash for field describe governor limit

    for (Integer idx = 0; idx <= 101; idx++)
        Account account = (Account)SmartFactory.createSObject('Account');

This example is simple one, in our case we are creating many different sobject types. So crossing 100 field describe limit is super easy.

We need caching support in SmartFactory for the describe information.

[abhinavguptas]

Added a pull request with a caching fix for this issue : #4