moved issue_url generation into view and changed issues list to accept dict with issue: issue; attributes: issue_url

Refactor pagination

See merge request !77

Added an optional lazy parameter to gitlab functions in views.py

See merge request !76

added optional lazy= parameter to gitlab_get_project function calls and gitlab_get_issue issue calls

Add pagination to project detail view

See merge request !75

moved issue_detail url generation to ProjectDetailView view (vs project_detail template). created a dict for issues list and generated urls, assigned in dict and retrieved in template