(GH-353) Revert back to puppetAgentDir setting

This restores the original setting name for the installation directory
where the extension can find the source files for the language server to
function. This allows us to ship a small release before we ship a
larger release with breaking changes later.

Author: jpogran

package.json

@@ -276,7 +276,7 @@
             "agent"
           ]
         },
-        "puppet.installDirectory": {
+        "puppet.puppetAgentDir": {
           "type": "string",
           "default": null,
           "description": "The fully qualified path to the Puppet agent install directory. For example: 'C:\\Program Files\\Puppet Labs\\Puppet' or '/opt/puppetlabs/puppet'"

src/configuration.ts

@@ -37,8 +37,8 @@ export class ConnectionConfiguration implements IConnectionConfiguration {
   }
 
   get puppetBaseDir(): string {
-    if (this.config['installDirectory'] !== null) {
-      return this.config['installDirectory'];
+    if (this.config['puppetAgentDir'] !== null) {
+      return this.config['puppetAgentDir'];
     }
 
     let programFiles = PathResolver.getprogramFiles();