Fix some display / API issue

[Neylix]

Description

Fix some issue affecting explorer and API

• %GetBalance message: amount serialized in float instead of integer, it was returning number in scientific notation (3e8) but this notation is not handled in Absinthe serialization.
• Metric poller : when using upnp, some router do not open port for local request on public ip (public_ip:port does not work but local_ip:port does work). If not request metrics to iteself, changed ip to 127.0.0.1
• Oracle chain on explorer is firstly loaded in chronologic order, but when a new transaction comes, the transaction is prepended causing an inconsistencie in the transaction order

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

%GetBalance message return integer value correctly
Metric poller can fetch metric from local ip correclty

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules