Consolidate API versions

[mcupak]

The API consists of 2 files - beacon.yaml and openapi.yaml, which contain conflicting versions under info/version (1.0.0 vs. 0.4.0).

[mcupak]

The files are actually not that large - should we just merge them into a single file to avoid this problem?

Also, should we distinguished between released and developed versions? E.g. similarly to what Maven does with -SNAPSHOT.

[sdelatorrep]

We split into 2 files for clarification (paths in a file and definitions in another) but it's totally true that they are not that big (around 600 lines in total). We can consider merging.

EDIT: If we merge both files, then #140 can be closed as it would not apply anymore.