[gjs: 1/2] Document how to run without installing

[Philip Chimento <pchimento src gnome org>]

commit ff0e498668bb46ae681fc653fb491bdb1bb76865
Author: Sonny Piers <sonny fastmail net>
Date:   Mon Mar 1 09:44:58 2021 +0100

    Document how to run without installing
    
    Closes #381

 CONTRIBUTING.md |  7 +------
 doc/Hacking.md  | 10 +++++++++-
 2 files changed, 10 insertions(+), 7 deletions(-)
---
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index fee21ad8..8783f348 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -84,11 +84,6 @@ Next, read the [workflow guide to contributing to GNOME][workflow].
 (In short, create a fork of the repository, make your changes on a
 branch, push them to your fork, and create a merge request.)
 
-If your contribution fixes an existing issue, please refer to the issue
-in your commit message with `Closes #123` (for issue 123).
-Otherwise, creating a separate issue is not required.
-See the section on "Commit messages" below.
-
 When you submit your merge request, make sure to click "Allow commits
 from contributors with push access".
 This is so that the maintainers can re-run the GitLab CI jobs, since
@@ -319,7 +314,7 @@ For further guidelines about line length and commit messages, read
 If the commit is related to an open issue in the issue tracker, note
 that on the last line of the commit message. For example, `See #153`, or
 `Closes #277` if the issue should be automatically closed when the merge
-request is accepted.
+request is accepted. Otherwise, creating a separate issue is not required.
 
 ## Thanks ##
 
diff --git a/doc/Hacking.md b/doc/Hacking.md
index 99031911..213f8112 100644
--- a/doc/Hacking.md
+++ b/doc/Hacking.md
@@ -12,6 +12,8 @@ For more information, see
 you'll need to manually format your code before it gets merged.
 You can also skip this step if you are not writing any C++ code.)
 
+## Dependencies
+
 GJS requires four other libraries to be installed: GLib, libffi,
 gobject-introspection, and SpiderMonkey (also called "mozjs78" on some
 systems.)
@@ -56,6 +58,12 @@ ninja -C _build
 Add any options with `-D` arguments to the `meson _build` command.
 For a list of available options, run `meson configure`.
 
+That's it! You can now run your build of gjs for testing and hacking with
+
+```sh
+LD_LIBRARY_PATH=_build GI_TYPELIB_PATH=_build ./_build/gjs-console script.js
+```
+
 To install GJS into the path you chose with `-Dprefix`, (or into
 `/usr/local` if you didn't choose a path), run
 `ninja -C _build install`, adding `sudo` if necessary.
@@ -141,7 +149,7 @@ To execute cppcheck, a static code analysis tool for the C and C++, run:
 ```sh
 tools/run_cppcheck.sh
 ```
-It is a versatile tool that can check non-standard code, including: variable 
+It is a versatile tool that can check non-standard code, including: variable
 checking, bounds checking, leaks, etc. It can detect the types of bugs that
 the compilers normally fail to detect.