Refactor logic around GL_ID.

Builds upon !8.

See merge request !9

Allow to configure location of the secret file

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

Write errors to stderr to get git to abort and show them as such.

Addresses private issues https://dev.gitlab.org/gitlab/gitlab-shell/issues/33 and https://dev.gitlab.org/gitlab/gitlabhq/issues/2195.

![Screen_Shot_2015-04-06_at_13.05.43](https://gitlab.com/gitlab-org/gitlab-shell/uploads/56a4b9f4cc983da93afeb2b85252ec7e/Screen_Shot_2015-04-06_at_13.05.43.png)

See merge request !8

Prevent character encoding issues by sending received changes as raw data.

Better alternative to !64 that doesn't require new gems and leaves dealing with string character encoding to gitlab-rails. See gitlab/gitlabhq!1701 for the corresponding changes there.

Fixes:

- https://github.com/gitlabhq/gitlabhq/issues/7486
- https://gitlab.com/gitlab-org/gitlab-ce/issues/858
- https://gitlab.com/gitlab-org/gitlab-ce/issues/877
- https://gitlab.com/gitlab-org/gitlab-ce/issues/965

See merge request !65

Correct spelling: Symlinking is short for symbolic linking

Remove recursive commands from bin/install

It is not clear what we need these for anymore. Because these commands
would recurse once through all existing files in all Git repositories,
and then another time through all directories these commands could
take very long on a server with a lot of repositories.

We keep the 'chmod' on config.repos_path, to deny world access to all
files and directories beneath it.

See merge request !63

It is not clear what we need these for anymore. Because these commands
would recurse once through all existing files in all Git repositories,
and then another time through all directories these commands could
take very long on a server with a lot of repositories.

We keep the 'chmod' on config.repos_path, to deny world access to all
files and directories beneath it.

Return true from GitlabPostReceive to ensure custom hooks run.

Fixes https://gitlab.com/gitlab-org/omnibus-gitlab/issues/438.

See merge request !62

Update readme after Saturday morning conversation with Dmitriy.

See merge request !61

Less if-else nesting in gitlab_shell.rb

This intention of this change is to make the normal flow of execution
easier to read, and to prevent mistakes in deeply nested if-else trees.

See merge request !60

This intention of this change is to make the normal flow of execution
easier to read, and to prevent mistakes in deeply nested if-else trees.

Expect broadcast message API endpoint to return 200 with empty JSON if
no broadcast messages available