Create a page to HLM resources

[glemieux]

Is your feature request related to a problem? Please describe.
There isn't a single page that points users to tools that may be necessary to develop more complex cases (e.g. sub-setting).

Describe the solution you'd like
We should provide a clear and concise page that provides links to HLM tools and related resources. Include in the References major chapter.

Describe alternatives you've considered
Create a reference page to pin on the github discussions board. I think this could be help as well and probably should be cross posted to the user's guide.

Additional context
Tool references are diverse enough (i.e. websites versus links to google docs) that having a common location to reference by link would be ideal.

[glemieux]

Issue #7 might be relevant to fold into here as well.

[glemieux]

Example of a resource link to google doc, in this case high-res, sparse grid, regional grids: https://docs.google.com/document/d/1kyd0AFNi3YcuzWbcHVtxAV3DHVM7O3amRl1agKcsf3Q/edit