Update Orion node readme
Node: bump version to v0.0.28
Merge branch 'node_fixes'
Bug 427310 - [eslint] report unused parameters
Bug 431769 - Get C syntax coloring for .ino files
Bug 424372 - global installation vs local installation

Basic framework for Orion global node installation.

Uses the current working directory when "orion" is invoked.

To test:
```
cd modules/orionode
./build/make-publish.sh tempfolder
cd tempfolder
npm pack
sudo npm install -g orion-0.0.27.tgz
```
Can then run "orion" from any directory that has the right permissions.

Signed-off-by: Kaitlin Huben <kaitlin.huben@gmail.com>
Bug 424372 - global installation vs local installation

Creates a global installation for Orion node.

To test:
```
cd modules/orionode
./build/make-publish.sh tempfolder
cd tempfolder
npm pack
sudo npm install -g orion-0.0.27.tgz
```

Can then run "orion" from any directory. Current functionality includes:
- ```orion```: launches orion on port 8081 using current working directory
- ```orion <workspaceDir>```: launches orion on port 8081 using workspaceDir
- ```orion -p <portno>```: launches orion on portno using cwd
- ```orion <workspaceDir> -p <portno>```: launches orion on portno using workspaceDir
- ```orion -w <workspaceDir> -p <portno>```: same as above, except order can be switched

Error thrown & exit if workspaceDir cannot be found/opened.

Signed-off-by: Kaitlin Huben <kaitlin.huben@gmail.com>