Now it tries to download whenever a service of its type is published on the network.
Merge branch 'develop' into network

Conflicts:
	MainWindow.py
	Sections.py
Merge branch 'gui' into network

Conflicts:
	Sections.py
Merge branch 'network' into develop
GetKeySection: Hardcoded the download_key_http function for now to return a public key from file
GetKeySection: Made it to import a key from a local file into a temporary
keyring. Made it to also verify if the key imported has the same fingerprint
as the one that was scanned(in this case hardcoded in on_button_clicked).
Added a TmpKeyring class that inherits TempKeyring (and also Keyring) from monkeysign module.This is because the import_data method from monkeysign.gpg.Keyring doesn't offer a way to import a key from a file, or I do not know how to use it properly.
GetKeySection: removed unnecessary class TmpKeyring and made it work with monkeysign's TempKeyring class.
It now imports the public key from a key text not from a file.
GetKeySection: put the key verification code into a function to make it more modular.
Publishing the avahi service is now done only when user request it, that means when user is navigating to the page that presents the key fingerprint and QR code.
Added an additional check to verify which button is pressed before publishing the service
Merge branch 'network_key_verify' into network
Made the tree view responsive to row selection changes to allow the user to advance in signing a key only after he selects one. This scenario can be improved to allow multiple key selection
SignPages: made KeyDetailsPage to display all UIDs for a selected key
KeyDetailsPage: made it to display all the signatures of a key
KeyDetailsPage: made it to display the expiration date for selected key
Merge branch 'gui' into develop

Conflicts:
	Sections.py
	SignPages.py