chore/Allow for a different server port via env var (Unstructured-IO#410)

Closes Unstructured-IO#409 

Use PORT in app-start.sh to allow us to change the server port.

To verify, make sure that these commands both run the server at the
expected port:

```
make docker-build

docker run -p 9200:9200 -e PORT=9200 -it --rm pipeline-family-general-dev:latest
curl localhost:9200/healthcheck
{"healthcheck":"HEALTHCHECK STATUS: EVERYTHING OK!"}

docker run -p 8000:8000 -it --rm pipeline-family-general-dev:latest
curl localhost:8000/healthcheck
{"healthcheck":"HEALTHCHECK STATUS: EVERYTHING OK!"}
```

Author: awalker4

CHANGELOG.md

@@ -1,5 +1,6 @@
-## 0.0.67-dev1
+## 0.0.67
 
+* Allow for a different server port with the PORT variable
 * Change pdf_infer_table_structure parameter from being disabled in auto strategy.
 
 ## 0.0.66

README.md

@@ -407,7 +407,13 @@ docker pull downloads.unstructured.io/unstructured-io/unstructured-api:latest
 Once pulled, you can launch the container as a web app on localhost:8000.
 
 ```bash
-docker run -p 8000:8000 -d --rm --name unstructured-api downloads.unstructured.io/unstructured-io/unstructured-api:latest --port 8000 --host 0.0.0.0
+docker run -p 8000:8000 -d --rm --name unstructured-api downloads.unstructured.io/unstructured-io/unstructured-api:latest
+```
+
+You can pass in a PORT variable to run the server on a different port in the container.
+
+```bash
+docker run -p 9500:9500 -d --rm --name unstructured-api -e PORT=9500 downloads.unstructured.io/unstructured-io/unstructured-api:latest
 ```
 
 ## Security Policy

scripts/app-start.sh

@@ -1,5 +1,7 @@
 #!/usr/bin/env bash
 
+export PORT=${PORT:-8000}
+
 NUMREGEX="^[0-9]+$"
 GRACEFUL_SHUTDOWN_PERIOD_SECONDS=3600
 TIMEOUT_COMMAND='timeout'
@@ -21,8 +23,9 @@ fi
 
 ${OPTIONAL_TIMEOUT} \
     uvicorn prepline_general.api.app:app \
-	    --log-config logger_config.yaml \
-        --host 0.0.0.0
+    --log-config logger_config.yaml \
+    --host 0.0.0.0 \
+    --port "$PORT"
 
 echo "Server was shutdown"
 [ -n "$MAX_LIFETIME_SECONDS" ] && echo "Reached timeout of $MAX_LIFETIME_SECONDS seconds"