Initial Swagger related changes from GSOC 2019 contrib (FINERACT-733)

This commit does not yet provide the full Swagger requirement, as was
outlined in FINERACT-733, but it's a first step forming the basis of
more to come (hopefully).  Here's the original PR description (but
note that some of this is about to be reverted in the next commit):


Reflected all API descriptions on swagger UI.

Formatted API descriptions.

Added swagger docs for new APIs.

Added swagger-gradle-plugin for automatic save of json during build.

Leveraged swagger codegen for generation of language-specific libraries
using gradle-swagger-generator plugin.

fineract-provider/build.gradle

@@ -43,9 +43,12 @@ buildscript {
      classpath 'com.radcortez.gradle:openjpa-gradle-plugin:3.1.0'
      classpath 'gradle.plugin.org.nosphere.apache:creadur-rat-gradle:0.2.2'
       classpath "com.github.spotbugs:spotbugs-gradle-plugin:2.0.1"
-      //Use Guava version 23+ as a workaround to spotbug intergration. 
+      //Use Guava version 23+ as a workaround to spotbug intergration.
       // See: https://github.com/spotbugs/spotbugs-gradle-plugin/issues/128#issuecomment-535864882
-      classpath 'com.google.guava:guava:28.1-jre' 
+      classpath 'com.google.guava:guava:28.1-jre'
+
+      classpath "io.swagger.core.v3:swagger-gradle-plugin:2.0.8"
+      classpath "gradle.plugin.org.hidetake:gradle-swagger-generator-plugin:2.18.1"
   }
 }
 
@@ -59,6 +62,8 @@ apply plugin: 'eclipse'
 apply plugin: 'idea'
 apply plugin: 'com.bmuschko.tomcat'
 apply plugin: 'project-report'
+apply plugin: 'java'
+apply plugin: "org.hidetake.swagger.generator"
 apply plugin: 'java-library'
 apply plugin: 'openjpa'
 apply plugin: "com.github.spotbugs"
@@ -69,7 +74,7 @@ dependencyManagement {
   imports {
     mavenBom 'org.springframework:spring-framework-bom:5.1.10.RELEASE'
   }
-  
+
   dependencies {
      dependency 'org.springframework.security.oauth:spring-security-oauth2:2.3.6.RELEASE'
      dependency 'org.apache.openjpa:openjpa:3.1.0'
@@ -207,6 +212,7 @@ rat {
 	'**/docs/system-architecture/**/*.xml',
 	'**/bootstrap-3.0.0/assets/application.js',
 	'**/system-architecture/js/plugins.js',
+    '**/docs/interoperation/specification/json/*.json',
 
 	//Apache License
 	'**/bootstrap-3.0.0/assets/less.js',
@@ -529,3 +535,30 @@ tasks.withType(SpotBugsTask) {
     reports.html.enabled = true
     reportLevel = "high"
 }
+
+// This is to save json file at build time
+resolve {
+    outputFileName = 'response.json'
+    outputFormat = 'JSON'
+    prettyPrint = 'TRUE'
+    classpath = sourceSets.main.runtimeClasspath
+    resourcePackages = ['org.apache.fineract']
+    outputPath = '/src/main/resources/swagger-ui/response.json'
+}
+
+//This is for code and swagger UI generation
+dependencies {
+    swaggerCodegen 'io.swagger:swagger-codegen-cli:2.4.2'             // Swagger Codegen V2
+    swaggerCodegen 'io.swagger.codegen.v3:swagger-codegen-cli:3.0.5'  // or Swagger Codegen V3
+    swaggerCodegen 'org.openapitools:openapi-generator-cli:3.3.4'     // or OpenAPI Generator
+    swaggerUI 'org.webjars:swagger-ui:3.10.0'
+}
+
+swaggerSources {
+    fineract {
+        inputFile = file('src/main/resources/swagger-ui/response.json')
+        code {
+            language = 'java'
+        }
+    }
+}