Main changes

• Improved handling of base tags as discussed in issue #225 and #181
• Upgraded to version 0.3.5.6 of d3 as described in issue #221
• Possible to set logLevel from configuration as described in issue#220
• Possibility to set with of generated images using the CLI as discussed in issue #204
• Support for font-awesome as described in issue #49 * end is allowed as substring in the vertex/node id asdescribed in issue #184

Code changes

• Modernized build environment
• Support for es2015 syntax via babel