Refactor grantbot's name, helper methods and collaborators instantiation

[camposer]

Is your refactoring related to a problem? Please describe.
The grantbot class has several pending improvements in order to make it easier to read.

• Name. The project name changed from grantbot to accessbot, but that's not reflected in the code yet
• Helper methods. The class is the core of the project, and all the logic there makes it hard to read
• Collaborators instantiation. Singleton methods implementation on the different collaborator files is ugly and can be avoided.

Describe the solution you'd like

• Name. Change the name of the project and validate tests
• Helper methods. Create separate class for each different command
• Collaborators instantiation. Remove singletons and transfer responsibility to the accessbot class