feat(android): optimize module build

[m1ga]

• exclude example folder from dist zip
• clean build folder (currently only dist folder was cleaned)

Advantages:

• when building modules with bigger examples like https://github.com/tidev/ti.compression/pull/250 it won't include all the example data
• currently if you have increase the version number in the manifest and build the module again it will include the old version unless you run ti clean. Its not a problem for the module but it increases the files size for no reason

Test:

• clone https://github.com/tidev/ti.compression
• build the android module
• check the dist/zip -> no example folder
• raise manifest version number
• build again without cleaning
• check dist zip. should only show the new version number

wrong zip:

(5.4.0 shouldn't be included)