VM-alloc branch-and-bound

Added an example for new the config syntax.

Previous configs used the old syntax, where all the allocators where automatically "Branch-and-bound" type in the config.

Added some sample outputs for various configurations.

Cleaned up VM and PM ID usage.

The IDs are not used in the BnB algorithm directly anymore.

The allocation is now a hash map with VMs as keys and PMs as values.

The non-fitting VMs are stored in Change.h directly.

The initialPM variable of VMs is set in the constructor and used afterwards for comparisons.

The IDs, however, are used for printing allocations (according to ascending order of VM IDs).

Other changes:
- Improved the VMAllocator interface
- Best cost is now uniformly -1 when no valid allocation was found
- Moved parameter configuration logging to main.cpp and improved log formatting
- Removed global_params.h (is not required since revision 17)
- Renamed some variables and functions for better understanding

Improved class hierarchy.

Added base class for allocator parameters and derived the BnB and ILP parameter classes from here.

VMAllocator is now an interface. The BnB and ILP allocators implement this interface.

Updated the config parser to handle the polymorphic parameter classes.

ILP solvers are configured in the config file similarly to BnB solvers.

Updated the sample config file.

Evaluation improvements and fixes.

- Changed active hosts coefficient to 10
- Added initial lower bound computation
- Migration limit is now a ratio
- Tests for multiple sizes in steps available
- Input problem data written to csv
- Cost component data written to csv
- lp_solve path can be configured
- Fixed crash when gurobi couldn't find a result
- Limited gurobi to 1 thread
- Fixed a VM sorting bug

Intelligent bound now available.

If enabled, the allocator solves a relaxed problem after every allocation.

This is done in order to determine a more accurate lower bound for the complete allocation.

Minor changes:
- Added intelligentBound parameter to configParser
- Problem instance ID is now logged in main.cpp
- Introduced additional VM counter in PM.h, required for bounding
- Updated TODO

Hotfix for PM comparators.

Fixed PM order when one PM is off and the other one is on (this was wrong in all comparators).

Fixed the case where both PMs are off for the sum comparator.

Improved PM sorting.

PM sorting now differentiates between PMs which are on/off.
-> PMs on are sorted in ascending order and put at the start of the list.
-> PMs off are sorted in descending order and put at the end of the list.

Also fixed a typo in the SortType enum.

Added simplistic configuration file support.

A sample config file is added for demonstration purposes.

Other minor modifications:
- Added toString function for SortType
- Hotfix for unsafe function sprintf
- Added WIN32 defines for ILP solvers
- Updated makefile
- Added header guard to ProblemGenerator.h
- Updated VS project

ProblemGenerator can now do a First-Fit allocation so that the generated initial mapping is not that bad