docs: fixes from 'first time' review (#2999)

docs/app-dev/app-architecture.md

@@ -5,7 +5,7 @@ Tendermint blockchain application.
 
 The following diagram provides a superb example:
 
-<https://drive.google.com/open?id=1yR2XpRi9YCY9H9uMfcw8-RMJpvDyvjz9>
+![](../imgs/cosmos-tendermint-stack-4k.jpg)
 
 The end-user application here is the Cosmos Voyager, at the bottom left.
 Voyager communicates with a REST API exposed by a local Light-Client

docs/app-dev/ecosystem.md

@@ -1,11 +1,9 @@
 # Ecosystem
 
 The growing list of applications built using various pieces of the
-Tendermint stack can be found at:
+Tendermint stack can be found at the [ecosystem page](https://tendermint.com/ecosystem).
 
-- https://tendermint.com/ecosystem
-
-We thank the community for their contributions thus far and welcome the
+We thank the community for their contributions and welcome the
 addition of new projects. A pull request can be submitted to [this
 file](https://github.com/tendermint/tendermint/blob/master/docs/app-dev/ecosystem.json)
 to include your project.

docs/introduction/what-is-tendermint.md

@@ -70,10 +70,6 @@ Tendermint is in essence similar software, but with two key differences:
   the application logic that's right for them, from key-value store to
   cryptocurrency to e-voting platform and beyond.
 
-The layout of this Tendermint website content is also ripped directly
-and without shame from [consul.io](https://www.consul.io/) and the other
-[Hashicorp sites](https://www.hashicorp.com/#tools).
-
 ### Bitcoin, Ethereum, etc.
 
 Tendermint emerged in the tradition of cryptocurrencies like Bitcoin,