Merge pull request #24 from StellarTools/feature/13-stellar-env

Added StellarEnv to manage and communicate with stellar installed versions

#13: disabled mark as prerelease

#13: Updated install.sh script to install stellarenv

Merge pull request #19 from InterstellarTools/feature/fix-release-zip…

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Fix zip step in build-and-release.yml

Merge pull request #19 from InterstellarTools/feature/fix-release-zip…

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Fix zip step in build-and-release.yml

Merge pull request #19 from InterstellarTools/feature/fix-release-zip…

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Fix zip step in build-and-release.yml

Merge pull request #19 from InterstellarTools/feature/fix-release-zip…

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Fix zip step in build-and-release.yml