update readme with i2p infra information

[bonedaddy]

:construction_worker: Purpose

We relaunched our I2P infrastructure, so the readme needs to be updated

:rocket: Changes

• Expand web interfaces section to list the current web interface and api endpoints
• Add clearnet and i2p sections to the endpoints

:warning: Breaking Changes

None

[codecov[bot]]

Codecov Report

Merging #486 into master will decrease coverage by 0.37%. The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #486      +/-   ##
==========================================
- Coverage   52.83%   52.46%   -0.36%     
==========================================
  Files          43       43              
  Lines        4371     4371              
==========================================
- Hits         2309     2293      -16     
- Misses       1549     1563      +14     
- Partials      513      515       +2     

Impacted Files	Coverage Δ
queue/ipfs_cluster.go	52.64% <0.00%> (-16.84%)	:arrow_down:

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