update to rails 4.1.5
Merge pull request #167 from DefactoSoftware/rails4.1.5

update to rails 4.1.5
validate that hours are integers (fix #168)
Merge pull request #169 from DefactoSoftware/validate-hours-integer

validate that hours are integers (fix #168)
add translation for helpful header (fix #166)
Merge pull request #170 from DefactoSoftware/helpful-i18n

add translation for helpful header (fix #166)
correctly remove no-categories message after adding one
Merge pull request #171 from DefactoSoftware/fix-projects-caching

correctly remove no-categories message after adding one
update chartJS with rails-assets.org to 1.0.1.beta.4
Merge pull request #115 from DefactoSoftware/upgrade-chart-js

[READY] Upgrade chart.js
implement tags overview
refactor calculating hours spent and percentages
remove legends and do some styling
Rename entry_stats methods
Merge pull request #173 from DefactoSoftware/tags-overview

[READY] Implement tags overview
upgrade to ruby 2.1.3
Merge pull request #185 from DefactoSoftware/ruby-2.1.3

upgrade to ruby 2.1.3
let users enter a description with hashtags when entering time
autocomplete hashtags
mention tags in the description placeholder