split up everything into 'full' and 'basic' build flavor

"full" is the original F-Droid app with all the features.  It should still
build the exact same app after this change.  "basic" is the smallest
version of F-Droid possible.  It does not yet build, nor work.

app/build.gradle

@@ -15,6 +15,9 @@ def getVersionName = { ->
 def isCi = "true".equals(System.getenv("CI"))
 def preDexEnabled = "true".equals(System.getProperty("pre-dex", "true"))
 
+def fullApplicationId = "org.fdroid.fdroid"
+def basicApplicationId = "org.fdroid.basic"
+
 android {
     compileSdkVersion 27
     buildToolsVersion '27.0.3'
@@ -31,6 +34,20 @@ android {
         }
     }
 
+    flavorDimensions "base"
+    productFlavors {
+        full {
+            dimension "base"
+            applicationId fullApplicationId
+            resValue "string", "applicationId", fullApplicationId
+        }
+        basic {
+            dimension "base"
+            applicationId basicApplicationId
+            resValue "string", "applicationId", basicApplicationId
+        }
+    }
+
     compileOptions {
         compileOptions.encoding = "UTF-8"
     }
@@ -49,15 +66,13 @@ android {
     defaultConfig {
         versionCode 1003001
         versionName getVersionName()
-        applicationId 'org.fdroid.fdroid'
-        resValue "string", "applicationId", applicationId
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }
 
     buildTypes {
         debug {
             applicationIdSuffix ".debug"
-            resValue "string", "applicationId", defaultConfig.applicationId + applicationIdSuffix
+            resValue "string", "applicationId", fullApplicationId + applicationIdSuffix
             versionNameSuffix "-debug"
             println 'buildTypes.debug defaultConfig.versionCode ' + defaultConfig.versionCode
         }
@@ -125,13 +140,10 @@ dependencies {
     implementation 'com.nostra13.universalimageloader:universal-image-loader:1.9.5'
     implementation 'com.google.zxing:core:3.3.2'
     implementation 'eu.chainfire:libsuperuser:1.0.0.201602271131'
-    implementation 'cc.mvdan.accesspoint:library:0.2.0'
     implementation 'info.guardianproject.netcipher:netcipher:2.0.0-alpha1'
     implementation 'info.guardianproject.panic:panic:0.5'
     implementation 'commons-io:commons-io:2.5'
     implementation 'commons-net:commons-net:3.5'
-    implementation 'org.jmdns:jmdns:3.5.3'
-    implementation 'org.nanohttpd:nanohttpd:2.3.1'
     implementation 'ch.acra:acra:4.9.1'
     implementation 'io.reactivex:rxjava:1.1.0'
     implementation 'io.reactivex:rxandroid:0.23.0'
@@ -142,10 +154,14 @@ dependencies {
     implementation 'com.fasterxml.jackson.core:jackson-annotations:2.8.7'
     implementation 'com.fasterxml.jackson.core:jackson-databind:2.8.7'
 
-    implementation 'org.bouncycastle:bcpkix-jdk15on:1.59'
     implementation 'org.bouncycastle:bcprov-jdk15on:1.59'
+    fullImplementation 'org.bouncycastle:bcpkix-jdk15on:1.59'
+    fullImplementation 'cc.mvdan.accesspoint:library:0.2.0'
+    fullImplementation 'org.jmdns:jmdns:3.5.3'
+    fullImplementation 'org.nanohttpd:nanohttpd:2.3.1'
 
     testImplementation 'org.robolectric:robolectric:3.8'
+    testImplementation 'org.bouncycastle:bcprov-jdk15on:1.59'
     testImplementation 'junit:junit:4.12'
     testImplementation 'org.mockito:mockito-core:2.7.22'