XD-111 Create final distribution zip across multiple projects

- Add separate application plugin task for dirt, gemfire & redis
- Move the script files into specific script direcories
- Add redis project that has the 2.6.13 source dist/structure
add redis installation script
XD-111 Create final distribution zip across multiple projects

- Combine the install directories of redis, gemfire & xd under dist/spring-xd
- Update gitignore
XD-111

- Add zip task to make spring-xd install archive
XD-111 Bundle spring-xd

- Fix install directories for projects
- Fix install-redis script: not to run 'make install' to respect existing redis install
- Fix install-redis script: copy executables into redis install bin directory
Merge remote-tracking branch 'springsource/master' into xd-111

Conflicts:
	build.gradle
XD-111

Not to include directory name 'install' inside the bundle
XD-111
 Add the bundle zip into spring-xd
XD-104 & XD-105

Add README & LICENSE files for Spring-XD distribution
Merge remote-tracking branch 'springsource/master' into xd-111
Merge pull request #17 from ilayaperumalg/xd-111