Support install task and SNAPSHOT version

* Add installAll, uploadArchivesAll, cleanAll build tasks. 
* installAll: should be used for building locally
* uploadArchivesAll: to be used for uploading to remote artifactory
* cleanAll: will call clean task of each build.gradle

Example:
// the following command will upload a SNAPSHOT version to the artifactory
// gradle/maven will update "SNAPSHOT" in the version number with the current datetime
>gradlew installAll -DMAVEN_UPLOAD_VERSION=0.0.0-SNAPSHOT -DMAVEN_UPLOAD_REPO_URL=http://thaliartifactory.cloudapp.net/artifactory/libs-snapshot -info

Bug Fixes:
* Fix generation of java doc jars
Why is only ThaliDeviceHub/android exempted? Shouldn't ThatliDeviceHub/Java also be exempted?