Add ./configure option to disable toggle versions

I consider this way cleaner than setting some environment
variable in the build script. Per default, sonames are generated.
If ./configure is run with "--disable-soname-versions", no soname
versions will be generated. This is mainly useful for android, but
it might find some use for other environments without soname versioning
Update android build script

Use the --disable-soname-versions option for android
Merge pull request #119 from sonOfRa/sonames

 Add ./configure option to disable toggle soname versions