Abandon function patch

[DouglasHorn]

Fixes #issue_number 16

#16

Description

Add abandon() function to allow the return of funds from Telos Works proposals. Add information on clauses to the human-language contract.

Test scenarios

Testing is required

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have cleaned up the code in the areas my change touches
• My changes generate no new warnings
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings
• I have removed any unnecessary console messages