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This commit changes the upstream links for Goblin and Gomega to the
mirrored versions:

- https://github.com/stroeerdigitalpublishing/golang-goblin
- https://github.com/stroeerdigitalpublishing/golang-gomega

Increase all occurrences of expected code coverage *at least 90%* to 100%.
This is the result of a meeting held on 16th April 2018 with the
following attendees:

- Jens Neuse
- Özgür Ünal
- Bastian Berkner
- Christian Engel
- Farhad Karimi
- Alexander Jandousek

This commit adds a table of contents of all 2nd level headings to the
`README.md` file.

This commit adds an example `Makefile` to the README
(in the advanced usage section) and runs you through the hoops on why it
might be beneficial to have your code linted before building.

This commit adds the source for the quote about what the purpose of the
`golint` command is.

Changes after peer-review with Alexander Jandousek (alexanderj1988@github.com):

- Add `go vet` as additional rule that has to be passed on running `go lint`.

This commit adds the additional rule to the documentation (`README.md`).

This commit add the `Advanced usage` section to the README.md file.
It also adds a `code` example on how to specify a directory (where the
linting checks should take place).

This commit adds a missing colon to the README.md file.

This commit simply fixes bad grammar in the README.md.
Big thanks to Rupert Helbig, because he was so kind to review the doc.

This commit changes the links of the Passing Tests TOS section to the
respective jump marks (anchor links).

This commit adds a section on how to pass the *90% code coverage check*
and explains what you have to do and why this is a good idea.

This commit adds the section on how to pass the `golint` checks and also
adds explanation on why use `golint`.

This commit changes the header *`gofmt`* to *Passing `gofmt` checks*.

This commit adds an explanation on why we chose to enforce the usage of
`gofmt` to the `README.md`

Adds an example unit-test using the excellent
[Goblin Testing Framework](https://github.com/franela/goblin) to the
`README.md`.

This commit simply adds instructions you could copy and paste to get the
linter up and running in no time.

This commit introduces the script which injects the `go lint`
subcommands into the target system.