Update spec, readme and changelog for 3.0.8 release.

Author: jiuyangzhao

ChangeLog.txt

@@ -1,3 +1,16 @@
+3.0.8 (2018-05-22)
+---------------------------------------------
+- Update to Latest API specs:
+  - Namespace Files:
+    - Added new too_large error type for uploads.
+    - New documentation.
+  - Namespace Team:
+    - Add is_directory_restricted attribute to memberprofile, memberaddarg.
+    - Add new_is_directory_restricted to membersetprofilearg.
+  - Namespace Team_log:
+    - Additional documentation.
+- Add asAdmin to DbxTeamClientV2.
+
 3.0.7 (2018-04-13)
 ---------------------------------------------
 - Update to Latest API specs:
@@ -45,7 +58,6 @@
 - Add withPathRoot to DbxClientV2.
 - Make Android and GAE optional in OSGI Import-Package statements.
 
-
 3.0.6 (2018-01-14)
 ---------------------------------------------
 - Update to Latest API specs:

ReadMe.md

@@ -14,7 +14,7 @@ If you're using Maven, then edit your project's "pom.xml" and add this to the `<
 <dependency>
     <groupId>com.dropbox.core</groupId>
     <artifactId>dropbox-core-sdk</artifactId>
-    <version>3.0.7</version>
+    <version>3.0.8</version>
 </dependency>
 ```
 
@@ -23,7 +23,7 @@ If you are using Gradle, then edit your project's "build.gradle" and add this to
 ```groovy
 dependencies {
     // ...
-    compile 'com.dropbox.core:dropbox-core-sdk:3.0.7'
+    compile 'com.dropbox.core:dropbox-core-sdk:3.0.8'
 }
 ```