Updates to YahooFinanceWithAlert demo application:

commit 00e6384b496104f71cf461b4321ae4d484f49421
Author: Milind Barve <milind@datatorrent.com>
Date:   Wed Mar 12 17:46:56 2014 +0530

    Made changes to accept multiple exec statements instead of a single statement. #918

commit 7640ce7cf590298f7889fd1128367a6f1d3516f8
Author: Milind Barve <milind@datatorrent.com>
Date:   Wed Mar 12 17:45:56 2014 +0530

    Made changes to reflect the changes in DerbySQLStreamOperator to accept multiple exec statements. #918

commit 3502f8a7cbffc4e1422da142dd3a3502484e7911
Author: Milind Barve <milind@datatorrent.com>
Date:   Wed Mar 12 17:45:12 2014 +0530

    Made ticker symbols, price thresholds and smtp specific params configeurable. If smtp is not configured, the alerts are displayed on console. If smtp is configured, an smtp alert will be generated. #918

commit 71d3b8d750007774dc5b8009d3a8d184942c4e16
Author: Milind Barve <milind@datatorrent.com>
Date:   Wed Mar 12 17:41:54 2014 +0530

    Rearranged the code to call process_tuple instead of doing processing in process(). The operator can now be extended. #918

commit 8dc9c611b9482741277c109733b1dd2c4c010207
Author: Milind Barve <milind@datatorrent.com>
Date:   Wed Mar 12 17:40:57 2014 +0530

    Added functionality to generate alerts for multiple tickers based on duration since the last alert for that particular ticker. #918