WIP: Add global balance to state

[Hyjaz]

Create the following files in the overview folder:

• action-names.ts
• actions.ts
• reducer.ts
• epics.ts

Move the actionNames you have created in the action-names file inside electra folder, e.g.:

export const GET_GLOBAL_BALANCE = 'GET_GLOBAL_BALANCE'
export const GET_GLOBAL_BALANCE_SUCCESS = 'GET_GLOBAL_BALANCE_SUCCESS'
export const GET_GLOBAL_BALANCE_FAIL = 'GET_GLOBAL_BALANCE_FAIL'

To the action-names file you created in the overview folder. The same thing for the actions, reducer and epics you have created.