Feature to handle configuration files using YAML
modfied all run method in pipeline, to accept yaml format as configuration and subject file
added grp_model tag in group analysis output
changed grp_model_ to _grp_model_ tag
replaced yaml files for config_fsl and modified model generator to read yml files
gp symlinks
Merge branch 'development' of https://github.com/FCP-INDI/C-PAC into development

'added gp symlinks'
updated centrality output directories
updated regex substitution in pipeline datasink
changed merged 4d file names
Merge branch 'development' of https://github.com/FCP-INDI/C-PAC into development

added correct names to merged 4d files
ignore empty lines and lines commented in input text files
added exception in create_fsl_model for yaml files
added exception in create_fsl_model for yaml files
added version number in __init__.py
Merge branch 'release/version_0.1.8'