fix crash at summary issues page.

Add new method - get tags for all projects (Tag.all_tags)
Fix view hook for use new method
refactor model

View logic moved to view and helpers.
Tag links now use javascript for query search, and now not rewrite previous query setting in filters. Now it’s work for all pages issues, gantt and calendar
refactor model. fix spaces
refactor views. fix variable names
add settings use_contains

Now user can select method for filter tag string in database: «like» or «equal»
set version to 0.0.2
Merge branch 'release/0.0.2' into stable