[chore] Global server configuration overhaul (#575)

* move config flag names and usage to config package, rewrite config package to use global Configuration{} struct

Signed-off-by: kim <grufwub@gmail.com>

* improved code comment

Signed-off-by: kim <grufwub@gmail.com>

* linter

Signed-off-by: kim <grufwub@gmail.com>

* fix unmarshaling

Signed-off-by: kim <grufwub@gmail.com>

* remove kim's custom go compiler changes

Signed-off-by: kim <grufwub@gmail.com>

* generate setter and flag-name functions, implement these in codebase

Signed-off-by: kim <grufwub@gmail.com>

* update deps

Signed-off-by: kim <grufwub@gmail.com>

* small change

Signed-off-by: kim <grufwub@gmail.com>

* appease the linter...

Signed-off-by: kim <grufwub@gmail.com>

* move configuration into ConfigState structure, ensure reloading to/from viper settings to keep in sync

Signed-off-by: kim <grufwub@gmail.com>

* lint

Signed-off-by: kim <grufwub@gmail.com>

* update code comments

Signed-off-by: kim <grufwub@gmail.com>

* fix merge issue

Signed-off-by: kim <grufwub@gmail.com>

* fix merge issue

Signed-off-by: kim <grufwub@gmail.com>

* improved version string (removes time + go version)

Signed-off-by: kim <grufwub@gmail.com>

* fix version string build to pass test script + consolidate logic in func

Signed-off-by: kim <grufwub@gmail.com>

* add license text, update config.Defaults comment

Signed-off-by: kim <grufwub@gmail.com>

* add license text to generated config helpers file

Signed-off-by: kim <grufwub@gmail.com>

* defer unlock on config.Set___(), to ensure unlocked on panic

Signed-off-by: kim <grufwub@gmail.com>

* make it more obvious which cmd flags are being attached

Signed-off-by: kim <grufwub@gmail.com>

internal/processing/statustimeline.go

@@ -25,7 +25,6 @@ import (
 	"net/url"
 
 	"github.com/sirupsen/logrus"
-	"github.com/spf13/viper"
 
 	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
 	"github.com/superseriousbusiness/gotosocial/internal/config"
@@ -111,8 +110,8 @@ func StatusSkipInsertFunction() timeline.SkipInsertFunction {
 		nextItemAccountID string,
 		nextItemBoostOfID string,
 		nextItemBoostOfAccountID string,
-		depth int) (bool, error) {
-
+		depth int,
+	) (bool, error) {
 		// make sure we don't insert a duplicate
 		if newItemID == nextItemID {
 			return true, nil
@@ -148,8 +147,8 @@ func (p *processor) packageStatusResponse(statuses []*apimodel.Status, path stri
 
 	// prepare the next and previous links
 	if len(statuses) != 0 {
-		protocol := viper.GetString(config.Keys.Protocol)
-		host := viper.GetString(config.Keys.Host)
+		protocol := config.GetProtocol()
+		host := config.GetHost()
 
 		nextLink := &url.URL{
 			Scheme:   protocol,