created environment file, and added installation instructions to contributing.

Author: ledm

CONTRIBUTING.md

@@ -71,7 +71,7 @@ and submitting [bug reports][issues]
 about things that don't work, aren't clear, or are missing.
 If you are looking for ideas, please see the 'Issues' tab for
 a list of issues associated with this repository,
-or you may also look at the issues for [Data Carpentry][dc-issues], 
+or you may also look at the issues for [Data Carpentry][dc-issues],
 [Software Carpentry][swc-issues], and [Library Carpentry][lc-issues] projects.
 
 Comments on issues and reviews of pull requests are just as welcome:
@@ -130,17 +130,30 @@ Extensive instructions for building and viewing the pages locally can be found [
 ```bash
 # apt (Ubuntu/Devian)
 sudo apt install ruby-dev ruby-bundler
+```
+or
+```bash
 # dnf (Fedora/Redhat)
 sudo dnf install rubygem-bundler ruby-devel
-to install the required ruby packages and
+```
+
+Alternatively, there's an environment file available which can be installed in conda with:
+```bash
+conda env create -f environment.yml -n esmvaltool_tutorial
+```
+
+To install the required ruby packages, run the following command in the tutorial's
+main directory to build and serve the website locally.:
 ```bash
 make serve
 ```
-to build and serve the website locally. The output on the terminal will contain a line similar to
+
+The output on the terminal will contain a line similar to:
 ```
 Server address: http://127.0.0.1:4000
 ```
-open the address in your browser to preview the website.
+This address can be opened in your browser to preview the website.
+
 
 ## Other Resources
 

environment.yml

@@ -0,0 +1,35 @@
+name: tutorial
+channels:
+  - conda-forge
+  - defaults
+dependencies:
+  - _libgcc_mutex=0.1=conda_forge
+  - _openmp_mutex=4.5=0_gnu
+  - binutils_impl_linux-64=2.33.1=h53a641e_8
+  - binutils_linux-64=2.33.1=h9595d00_17
+  - ca-certificates=2019.11.28=hecc5488_0
+  - gcc_impl_linux-64=7.3.0=hd420e75_5
+  - gcc_linux-64=7.3.0=h553295d_17
+  - gdbm=1.18=h0a1914f_1
+  - gmp=6.2.0=he1b5a44_2
+  - gxx_impl_linux-64=7.3.0=hdf63c60_5
+  - gxx_linux-64=7.3.0=h553295d_17
+  - icu=64.2=he1b5a44_1
+  - ld_impl_linux-64=2.33.1=h53a641e_8
+  - libffi=3.2.1=he1b5a44_1006
+  - libgcc-ng=9.2.0=h24d8f2e_2
+  - libgomp=9.2.0=h24d8f2e_2
+  - libiconv=1.15=h516909a_1005
+  - libstdcxx-ng=9.2.0=hdf63c60_2
+  - libxml2=2.9.10=hee79883_0
+  - libxslt=1.1.33=h31b3aaa_0
+  - ncurses=6.1=hf484d3e_1002
+  - openssl=1.1.1d=h516909a_0
+  - rb-mini_portile2=2.4.0=hc42de5b_0
+  - rb-nokogiri=1.10.8=he0b3888_0
+  - readline=8.0=hf8c457e_0
+  - ruby=2.6.5=h305c5c1_0
+  - xz=5.2.4=h14c3975_1001
+  - yaml=0.1.7=h14c3975_1001
+  - zlib=1.2.11=h516909a_1006
+