A few minor fixes for Mavericks, SQLite build step for Python, and SciPy stack

I have attempted to make it easy to merge these changes with the existing the BuildEM master for FlyEM.

In the process of trying to get BuildEM to work on Mavericks, there were some changes needed. A subset of these have been included that should not affect other platforms. Note: I have not included all the changes as some of them are unique to Mavericks and others have not been included for various other reasons (i.e. no longer relevant, etc.). I have tested this build on a barebones Linux VM to be sure of this.

Also, in attempting to build iPython, I discovered that Python has an SQLite dependency ( https://docs.python.org/2/library/sqlite3.html ). I have included a CMake that will get SQLite to build and added it as a dependency of Python.

In addition, for my own needs, I have gotten the SciPy stack to build on my machine. In the process, I have generated some CMake files to get this to work. Though they may not be necessary for everyone, I have certainly found them useful. They will not be installed by default; however, if one wishes to install the whole stack easily, there is a scipy-stack pseudo-target that configures, builds and installs all the components.