remove unused imports from common.i
add WITH_EXAMPLES cmake flag

on by default so no regression
don't install json outputs
make all builds python

xml remains excluded from make all
parens in cmakelists
respect PYTHON_PREFIX
only install python wrapper libraries

for instance _libcasadi_core.so, not libcasadi_core.so and .so.2.0
debian build now makes python-casadi
shared library version starts at 0.0
Merge branch 'develop' of github.com:casadi/casadi into develop