Fix compilation when lib is not installed yet

Otherwise g-ir-scanner doesn't know where to find libapmonitor.so
Use a generic marshaller

No need for all that tooling.
Newer glib don't need g_type_init() to be called
Add clean target
Return corresponding icons for tech and signal strength
Add warnings to g-ir-scanner
Don't assert when failing to parse TXT data
Print icon names in test output
Add script to create fake hotspot data
Ignore local APs by default

If NetworkManager offers the AP status locally, then we don't
want to detect our own status, just the status of the AP running
on another machine.