added: linux default compile flags to enviroment 

 * added: linux default compile flags to enviroment …

  * added: linux, OSX enviroment: "MAKEOPTS" option to pass on to make for multi-core cpu build
build.sh

```
make $MAKEOPTS
```



++++++
The future idea would be to make some of those configurable through the .condarc
DID NOT YET IMPLEMENT IT

basically I want to set in the build.sh something like the above make $MAKEOPTS: my notebook has 4 cpu: so I want to be able to configure that in .condarc,

My standalone PC has 2 cpu.

So it is not good if such compile stuff is hard coded in the build.sh but better to be configurable globally in  .condarc