transaction example

This is a very simple example showing how to use TransactionManager. This example shows how to begin a transaction, commit a transaction, and rollback a transaction while showing exception handling. We commit two keys and rollback adding a third key and destroying an existing key while showing how to handle exceptions.

Prerequisites

Install Apache Geode
Build and install Apache Geode Native
Apache Geode Native examples, built and installed
Set GEODE_HOME to the install directory of Apache Geode

Running

From a command shell, set the current directory to the transaction directory in your example workspace.
```
$ cd workspace/examples/cpp/transaction
```
Run the startserver script to start the Geode cluster with authentication and create a region.
For Windows cmd:
```
$ powershell.exe -File startserver.ps1
```
For Windows Powershell:
```
$ startserver.ps1
```
For Bash:
```
$ ./startserver.sh
```

Execute cpp-transaction. The output will show the cache and region creation, up to five rolled back transactions, and finally the commit of the transaction if the maximum of five rollback were not executed. For example:

$ ./cpp-transaction
   Created cache
   Created region 'exampleRegion'
   Rolled back transaction - retrying(4)
   Rolled back transaction - retrying(3)
   Rolled back transaction - retrying(2)
   Committed transaction - exiting

$ ./cpp-transaction
   Created cache
   Created region 'exampleRegion'
   Rolled back transaction - retrying(4)
   Rolled back transaction - retrying(3)
   Rolled back transaction - retrying(2)
   Rolled back transaction - retrying(1)
   Rolled back transaction - retrying(0)

Run the stopserver script to gracefully shutdown the Geode cluster.
For Windows cmd:
```
$ powershell.exe -File stopserver.ps1
```
For Windows Powershell:
```
 $ stopserver.ps1
```
For Bash:
```
$ ./stopserver.sh
```