===== incr =====
Increment a numerical key’s value by the given number if the key/value pair exists.

**syntax:** 
<code>
incr <key> <value> [noreply]
</code>

**parameters**
  * **key** - The name of the unique key by which data is accessed.
  * **value** - The data that needs to be stored. This parameter needs to be given on the new line after executing the command with the above options.

**example:**
<code>
incr mykey 4

5
</code>

**output notes:**
  * **4** → Add 4 to the value of "mykey"
  * In this example, if "mykey" had a value of "1", after running **incr**, its value would be "5".

**possible errors:**
  * **NOT_FOUND** - Indicates that the provided key does not exist in the LSMCD server.
  * **CLIENT_ERROR** - Indicates that the value associated with the provided key is not numerical. 
  * **ERROR** - Indicates any other error such as a syntax error.