Create a basic common.h file for action_management

[ghost]

Create a new custom_actions_common.h file to store basic shared defines and include statements that all/most of the custom action module is going to need. Include basic error codes and UT hash/list imports that are needed now, and leave it open for more defines as needed.

[ghost]

Pushed a custom_action_commons.h file containing includes for basic std libraries, assert, math, uthash/list and common.

Also contains basic error codes defines for action block failure:

• NULL_BLOCK: The block that was passed in is NULL
• INVALID_ARGS: An invalid number of attributes were passed in for the action type
• INVALID_ATTRIBUTES: Something is wrong with at least one of the attribute pointers associated with the block
• OPERATION_ATTRIBUTE_MISMATCH: The operation the block has cannot be applied to the selected attributes (e.g. greater than comparisons on strings, or random number generation with chars)
• CONTROL_MISSING_END: A control block with a paired end (WHILE/ENDWHILE, IF/ENDIF) cannot find the respective end block in the path it goes down
• NO_TYPE: The block passed in does not have its block_type set correctly