Add changelog

[PVince81]

@DeepDiver1975 I preemptively added #125.

Will need to backport the changelog to stable10 as well

[DeepDiver1975]

hmm - this changelog is based on core but the app has a version itself and is released on the marketplace

shall we maintain 2 changelogs?

[PVince81]

@DeepDiver1975 good point... The core build will tag this repo with v10.0.3, etc version but marketplace has a different version...

Let's use only one changelog but with the app's own version scheme.

Later on once we have a bundling script we could build the core release by pulling the latest compatible "market" app.

[PVince81]

cc @pmaier1 @felixboehm in case you have better ideas ^

[PVince81]

we could use both versions in an entry: 10.0.3 / 1.2.3

[PVince81]

I added the second version as well, and increased the app version to 0.1.1.

When we replace "Unreleased" it will say "10.0.3 / 0.1.1".

If we need to release a new market version on the marketplace as a hotfix, then the changelog will have a new section "10.0.3 / 0.1.2"

@pmaier1 are you ok with this ?

[PVince81]

seems my changes got lost in a rebase

[PVince81]

stable10: bcecfcb

[patrickjahns]

I am a bit confused - since we already published 0.2.1 on marketplace: https://marketplace.owncloud.com/apps/market