Merge pull request #3879 from dbt-labs/emmyoop/update-contributing

Fixed typo and added some more setup details to CONTRIBUTING.md

CONTRIBUTING.md

@@ -68,7 +68,7 @@ The `dbt` maintainers use labels to categorize open issues. Some labels indicate
 
 - **Trunks** are where active development of the next release takes place. There is one trunk named `develop` at the time of writing this, and will be the default branch of the repository.
 - **Release Branches** track a specific, not yet complete release of `dbt`. Each minor version release has a corresponding release branch. For example, the `0.11.x` series of releases has a branch called `0.11.latest`. This allows us to release new patch versions under `0.11` without necessarily needing to pull them into the latest version of `dbt`.
-- **Feature Branches** track individual features and fixes. On completion they should be merged into the trunk brnach or a specific release branch.
+- **Feature Branches** track individual features and fixes. On completion they should be merged into the trunk branch or a specific release branch.
 
 ## Getting the code
 
@@ -135,7 +135,7 @@ brew install postgresql
 
 ### Installation
 
-First make sure that you set up your `virtualenv` as described in [Setting up an environment](#setting-up-an-environment). Next, install `dbt` (and its dependencies) with:
+First make sure that you set up your `virtualenv` as described in [Setting up an environment](#setting-up-an-environment).  Also ensure you have the latest version of pip installed with `pip install --upgrade pip`. Next, install `dbt` (and its dependencies) with:
 
 ```sh
 make dev
@@ -170,6 +170,8 @@ docker-compose up -d database
 PGHOST=localhost PGUSER=root PGPASSWORD=password PGDATABASE=postgres bash test/setup_db.sh
 ```
 
+Note that you may need to run the previous command twice as it does not currently wait for the database to be running before attempting to run commands against it.  This will be fixed with [#3876](https://github.com/dbt-labs/dbt/issues/3876).
+
 `dbt` uses test credentials specified in a `test.env` file in the root of the repository for non-Postgres databases. This `test.env` file is git-ignored, but please be _extra_ careful to never check in credentials or other sensitive information when developing against `dbt`. To create your `test.env` file, copy the provided sample file, then supply your relevant credentials. This step is only required to use non-Postgres databases.
 
 ```