feat(docs): various improvements

- removing spaces at end of line
- fixing spelling and grammar mistakes
- making sure 'Vikunja' is spelled the same way everywhere
- prefer using editors word wrap instead of hardcoding word wrap in markdown (reason: different word wrap per editor & end of line space)
- add newline add end where missing
- remove double colon at end of headlines
- remove unnecessary indention
- make sure code blocks and headlines etc always have an empty line around

docs/content/doc/development/metrics.md

@@ -34,14 +34,13 @@ promauto.NewGaugeFunc(prometheus.GaugeOpts{
 })
 {{< /highlight >}}
 
-Then you'll need to set the metrics initial value on every startup of vikunja.
+Then you'll need to set the metrics initial value on every startup of Vikunja.
 This is done in `pkg/routes/routes.go` to avoid cyclic imports.
 If metrics are enabled, it checks if a redis connection is available and then sets the initial values.
 A convenience function is available if the metric is based on a database struct.
 
 Because metrics are stored in redis, you are responsible to increase or decrease these based on criteria you define.
-To do this, use `metrics.UpdateCount(value, key)` where `value` is the amount you want to cange it (you can pass
-negative values to decrease it) and `key` it the redis key used to define the metric.
+To do this, use `metrics.UpdateCount(value, key)` where `value` is the amount you want to change it (you can pass negative values to decrease it) and `key` it the redis key used to define the metric.
 
 ## Using it