updated bowtie2 and grimaces

- bowtie2: in version 2.2.4 of bowtie2, more/other executables are present to check
- gromacs: removed inconsistencies for version >= 5.0
In easybuild/easyblocks/g/gromacs.py:

>          if LooseVersion(self.version) < LooseVersion('5.0'):
>              libnames = ['gmxana', 'gmx', 'gmxpreprocess', 'md']
> +            libdir = 'lib'
> +        else:
> +            libnames = ['gromacs']
> +            libdir = 'lib64'


This makes no sense. lib64 vs lib is decide by the system, not the version of GROMACS. Use the tuple version from the develop branch.

I just rebuilded both GROMACS/4.6.1-intel-2014a-hybrid and GROMACS/5.0.2-intel-2014a-hybrid on the same SL 6.6 system: the former generates a lib directory, the latter a lib64 directory...