Add a travis.yml to test a build.
Mac support in travis.yml
Check return values of malloc/realloc in zip_read

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Revert "Keep track of the minimum Depth / time on the planner."

This reverts commit 9a497b1cb0f38e8a7e04e29543da5241a38d2195.
Real fixup

Fixes: #358
WIP drop_stone_mode
Fix building in git shallow clones

If we are building from a shallow clone, just guess the version based on
whats hard-coded in VERSION and append a -git to show thats it somwhere
behind that.

Signed-off-by: Anton Lundin <glance@acc.umu.se>