ISIS-537 Bootstrapify wicketcharts

(cherry picked from commit 5eb8814301c3eb01dee0010695bd4e56dc8eca3b)
Issue #2 - Return null instead of failing with a NPE

(cherry picked from commit 67038fc0d5ee87ed46f1076b7ec4506af331f2bf)
ISIS-537 Remove dependency to profilestore
ISIS-537 Use font icon for the "View as" selector for collections

https://trello.com/c/YaU670zN/36-suggestion-i-wonder-if-the-view-selectors-on-the-far-right-eg-list-vs-summary-vs-gmap3-vs-hidden-should-instead-be-rendered-as-a
bumping version to 1.8.0-SNAPSHOT
changing dependency on Isis to 1.8.0-SNAPSHOT
depending on Isis 1.7.0; update to README in preparation for release of 1.7.0 of this module
bumping to 1.7.0
bumping to 1.7.1-SNAPSHOT
merging 1.8.0-bootstrappify with 1.7.0 release