Created generate_apklib.bat and mvn_install.bat

Easy Maven integration using the Android Maven apklib structure.
The generate_apklib batch file will use 7-zip to generate an apklib zip
file containing the files enumerated in apklib.txt.

mvn_install.bat will install aFileChooser to the local Maven repository
with the following information:

groupId: com.ipaulpro
artifactId: afilechooser
version: 1