Fix ssl=false parsing

ssl was mistakenly set to the string "false" instead of the Boolean false.

Author: sonicdoe

packages/pg-connection-string/index.js

@@ -61,7 +61,7 @@ function parse(str) {
     config.ssl = true
   }
 
-  if (config.ssl === '0') {
+  if (config.ssl === 'false' || config.ssl === '0') {
     config.ssl = false
   }
 

packages/pg-connection-string/test/parse.js

@@ -199,6 +199,12 @@ describe('parse', function () {
     var subject = parse(connectionString)
     subject.ssl.should.equal(true)
   })
+  
+  it('configuration parameter ssl=false', function () {
+     var connectionString = 'pg:///?ssl=false'
+     var subject = parse(connectionString)
+     subject.ssl.should.equal(false)
+   })
 
   it('configuration parameter ssl=1', function () {
     var connectionString = 'pg:///?ssl=1'