[Android] Update gitignore

[gujjwal00]

Updates gitignore file to exclude temporary/local files.

I also want to ignore .idea directory but skipped it as it is already in the tree. Maybe we can ignore specific files & directories inside .idea.

[gujjwal00]

@bk138 what do you think about ignoring .idea directory?

[bk138]

Does not seem overly important to me. What do the official guidelines say?

[gujjwal00]

It is important because Android studio generates a lot of temporary files in that directory and we have to avoid them on every commit.

Here is the .gitignore file of brand new Android Studio project:

*.iml
.gradle
/local.properties
/.idea/caches
/.idea/libraries
/.idea/modules.xml
/.idea/workspace.xml
/.idea/navEditor.xml
/.idea/assetWizardSettings.xml
.DS_Store
/build
/captures
.externalNativeBuild
.cxx

See: https://stackoverflow.com/questions/16736856/what-should-be-in-my-gitignore-for-an-android-studio-project

[bk138]

OK with me :-)